This is quite a long story we have here tbh, so I'll try to be as concise as possible.

For 2 years or so, we played in our friend's campaign setting, It was me, my brother, my BFF, the DM, a friend, and another friend me and my brother had in common for something like 8 or so years, which is the focus of today's story, we'll call them X for brevity.

To give context, X's character always was very... One-dimensional, imagine the classic edgy Drow rogue with no emotion whatsoever and you have it, backstory wise They weren't very developed either, our DM had to do the heavy lifting to add to it, but the core idea X had for the master was that their character was the lost prince of the Drows, imprisoned and experimented on for.... 350 years... Yeah, I told you they were edgy... In their imprisonment, they became the leader of a group of assassins for the new Elf King. So long story short they escaped and got recruited by a powerful mage to join our quest to save the world.

They never really engaged in any conversation if it wasn't about their character in some way, did things without any apparent reason, killed hostile people on sight when most of our party were neutral good, and tried to defuse the situation and their character's group of assassins had an awful history of killing my character's race which in the past caused her race (the wood elves) to retire to the woods and live their life as hermits in fear of them.

To give an idea of the type of crap X pulled, here's a short list of the worst things:

• Made up multiple things in the story without the DM's consent.
• Tried to literally explode in a wave of magic energy and possibly kill the whole party in the act without telling the DM, knowing full well that nothing in their character's kit enabled them to do so.
• Asked the mayor's hand in marriage after we dug them up from a dich, which mind you, a mayor that hated us and that we met the day prior, for no reason whatsoever, it wasn't even a bit.
• Left a specific item to be found by an entity that we knew full well that if found by said entity it would cause pandemonium which of course happened, and killed a ton of people and it happened two times.
• Slash the handoff of the head of the city guards, instead of just stopping them from hitting the barkeeper, who of course went berserk and arrested us all, but not after X's character killed the whole guard squad they had with them, and btw they still have their hand in their inventory.
• Threatened to cut the throat of my character while under the effect of a spell that only made them indifferent.
• Tried to kill the mayor of a city we just got in.
• Got addicted to a drug, without anybody knowing and tried to use it in combat, passing out as a result.
• Never talked with anybody about anything, the only time they did it was to ask them to join them in a genocide.
• Redirect the focus of the story to their backstory at any chance they get.
• While making a pyre for the fallen of a city that we tried to save my character tried to insight if X's character had any particular feelings about what happened in the city, and their response? They felt nostalgic looking at the burning corpses, and btw those people died because of them.

And all of this before they just straight up left the campaign for 7 months of radio silence.

So what's the problem if X is this problematic why am I so conflicted with the decision we took? The problem is that I've known X for 8 years, They aren't a bad person by any means, but they are very indifferent about the story of the campaign and does stuff without a real reason behind it, so we kick them out out of frustration, saying that even tho we don't want to play d&d with them anymore it doesn't mean we don't care about them or we don't want them as a friend anymore.

So... What are your thoughts about this situation? I like to think that we did the responsible thing, but I would like to know people's thoughts on this.

With the caveat that we only know your side of the story, it sounds like this could be justified. A lot of the behaviour you list constitutes major player red flags (which isn’t to say things like these are always bad—but they take a group which is cool with that kind of play), and the totality of them very well could be off putting and warrant removal.

When it comes down to it, however, whether the choice is right or wrong is not something strangers on the interwebs can answer.  So, just ask yourself this question: Was your group so upset with X’s presence that everyone will have more fun now that X is gone?

If the answer is “Yes, I think their behaviour’s effect on our enjoyment was so negative that we all are having vastly more fun now,” that shows you all probably did the right thing.

So they did a lot of stuff that annoyed you, then just disappeared? And after seven months of silence you've decided to kick them?

Kind of feels like they left of their own accord. If you mean that they came back after seven months, then I'd have thought what they'd done since would more relevant than what they did a year give or take) ago...so I'm a little confused as to what happened.

Regardless though, if they're trashing your game, then I get it. I don't know their side of the story, but even if they're retaliating for something...it seems like the situation has deteriorated too much, regardless of who the bad guy is.

Just be aware, and it seems you at least sense it, that this could blow up. This person could take offence and any protestation that your rejection is limited to D&D may not be given value or be believed.

Whether that's worth it to you is your call. We're not there. I just want you to know that it could easily end your friendship, because you may decide in a few months that it wasn't so bad after all...or you may not. 

We can't tell you what's right and what's wrong because we only have part of the story. We can just point out the consequences. From the sounds of it, if he were a stranger, I'd give him the boot...but your friendship is potentially part of the deal, so...

That's the issue, btw They did come back after 7 months, but those 7 months made us realise that we just played much better without them, We all agreed that their way of playing became so destructive that it was a hindrance to our enjoyment of the game, we did talk to them on multiple occasions before it became this much of a problem for the group, especially the DM tried, again and again, to explain to them what was "problematic" for us to play around, but nothing ever changed if anything things got worst, even out of the game they became quite distant before this whole ordeal. So we made our choice as a group after a year and a half of weekly sessions with them.

The first thing they did when they came back was to railroad the story (again) to what happened to their character while we were split and just being destructive in general, giving away our location to our enemies, coming back with an entire militia hunting them down and a lot of crap our DM had to deal with during a couple of sessions they had to catch up to the party.

And out of context, those things could be cool in a story, but if your character does random shit because of reasons all the time, doesn't interact with the story, everything is a meme and puts the party in danger all the time for the stupidest things they do, trust me it becomes annoying. It's okay to joke and to not always take things seriously, it's D&D the rest of the party does it all the time (to a lesser degree) but when we tell time and again, that that type of attitude towards the game is destructive to our enjoyment and nothing changes for more then a year it becomes frustrating. 

And I left out a lot of other stuff X did, it became so cringy and annoying to the point of us just zoning out while they did "their thing".

I know that doing so will probably "kill" our friendship and honestly I can't blame them for it, but at the same time our group feels like we did all we could to avoid this, but alas sometimes people don't match with some hobbies.

Part of your problem is the DM here.  The DM should be driving the game. The DM says what happens to the NPCs and determines their actions.  If I was a DM of a table where a PC caused this many problems and then disappeared for 7 months, that PC is now an NPC in my game and I am not going to spend time trying to get the player caught up.  Roll a nw character, and I will approve it being used in the game or not.

I mean again we only have one side of the story.

It sounds like during the 7 month break your group realized or at least had a consensus of what the issues you were all dealing with and agreed you didn't like them. Than X comes back and starts doing it again... during no time do you mention anyone trying to talk to him about said issues... which if he is/was a friend should have been a very important part of trying to resolve the issue. It doesn't mean that the issue would be fixed but it would have had at least a chance to defuse any hostilities that could exist in the aftermath.

It's not that easy, The problem wasn't that they had to catch up, it was X's approach at the table, We played in other settings with X and with other characters but it was always the same problem, at their core X took d&d as a joke, like if they were in an anime and they were the protagonist if you want, doing random stuff because "it's funny".

I can't blame our DM, they are genuinely hard to work with When I first DM'd for our group X drove me crazy with their insane ideas for their character and to find proof of that I made a post some time ago here asking for help on how to approach them and saying that the character they wanted wasn't feasible. Long story short they asked at the time to bring to the table a blind cannibal serial killer and the only thing he can see are the ghosts of who he ate..... In a detective story..... Where you're hired by the city's council to investigate stuff..... You can see how well that would play out.

We did try multiple times to talk to them about it, especially the DM, even after the 7-month break, but they never changed their approach.

Even if what the other player was doing wasn't necessarily wrong, it does sound like they were a very bad fit for your group.

Quote from 6thLyranGuard >>

Even if what the other player was doing wasn't necessarily wrong, it does sound like they were a very bad fit for your group.

 At the end of the day, I would say that it wasn't anybody's fault, they had their way of playing D&D (even if I'm still pissed off by some of their plays not gonna lie) and we have ours which sadly don't match, as I said they aren't a bad person or anything of the like, but to avoid the situation to degenerate further we had to kindly ask them to step out of the game, it wasn't the right fit for what they were looking for obviously, even in hindsight I think we would've done the same, we tried to talk it out at every step of the way, even when we asked them to step out, we did have a conversation about finding another way, which went nowhere, but we all tried.

I can't say that it's pretty to ask someone you have known for 8 years of your life to stop playing with you because you're not enjoying the time spent together but it was the best choice for everyone, it became so stressful at the end that most of our party dreaded our D&D night instead of enjoying it.

Same standard caveat: we only know your side.

I am surprised it took so long. 

I have a big group. It is made up of friends I have played off and on with since the early 80's, their kids, grand kids, and friends of all the different groups. 

Every now and then we get someone like that in one of the many different games (I am not the only DM, but I am the only one that only DMs).  The longest I have ever seen a player get away with that was in one of my games, and it was seven sessions, and the last three were because they were young.

When I talked to them, it was very much the same thig -- they weren't having fun, and part of why is that they game wasn't about them, and they really felt it should be. Despite several offers to give them dedicated storylines, they really just didn't want to do anything.

So, the players stopped inviting them. 

They came back about a year later, and after hearing about the exciting things going on, joined one of the other games in our group, where they are having a blast -- so it could have just been me, or the kind of game (a dungeon crawl) or just personal stuff on their part What matters is they disrupted the game for others, akin to walking into a monopoly or risk game and flipping the board.

Quote from AEDorsay >>

Same standard caveat: we only know your side. 

 True but to be fair I don't think there's a "side" to hear from, they did the things I pointed out, and it disturbed how everybody else played the game, we talked about it in great detail over the time we played and the reasons they did what they did came to: "I like doing stuff because it sounds fun, there isn't a criterion for what I do, most of the time I just do what I'm thinking at the moment", which isn't a bad way of playing D&D, tbh there isn't a wrong way to play this game, but it is a game that you play with friends and when your friends (DM included) on multiple occasions tell you how much it became a problem that way of playing with how the DM tells their story and how the rest of the party enjoys it, then it's a problem.

We tried to make it work to the best of our abilities (especially the DM) and it worked for them, from what I got from X they had fun while it lasted, but it took a toll on the rest of the group, especially after the 7 month period they left, like everything in life there isn't a right or wrong here, just an "I felt like this" type of stuff.

With the caveat of taking your Original Post as "fact".

What if it was a weekly group of an amateur sports team? - X wants to play and they're playing TO the rules, but against the spirit of the team.  No one's enjoying their interactions within the team and it's more fun when they're not there. 

You've all attempted to police their behaviour and they're not participating in a way that's been asked of them (repeatedly).  Other games are available and we live in the golden age of VTT's + accessible online games - there are plenty of them that X could be a better fit for.

it's a social game with social rules, they're being antisocial, at least in the context of your groups/social rules.  What I would say here is that you all, but the DM especially has a responsibility towards everyone that is showing up and following the Social Rules - you're focusing on the wrong player here.  You have a majority of players that are being penalised by X's presence.  X is curtailing their fun and the DM is passively allowing that to happen.  You've all talked about this and reached a conclusion - stick to it.

I think what you're really asking for her is advice on the actual friendship - because according to the "facts" you've presented, it's easily the right call - more happiness for more people.  Personally, I don't play D&D with irl friends - my irl social group just isn't into D&D, but I don't show up to their Sunday football (soccer) games either and that's fine, we still hang out, go for beers, listen to music - normal friend stuff and sometimes our interests cross over and sometimes not.  A couple of friends are on the same Sunday football thing and they talk about it when we're down the pub and I'll ask questions participate socially in the chit chat and all that normal stuff, but I've no interest in football and I'm not gonna turn up on a nice sunny Summer Sunday morning to do it (even if it does end up in the pub) and I'm definitely not showing up on a rainy, cold Autumn morning to do it either and that's fine too.  I'm happy for soccer friends and I think vice/versa.

You know far more about this than us, but you say you think it'll be "the end of the friendship" - to be clear???  That's on them then.  That's a choice they can make and if I'm offering advice, I'd suggest making it explicit to them that "hey, we can still hang out and still do stuff and I/we do still want to - just not this D&D game".  I'd do that as a group, everyone together "you're a good friend, want a beer on...  (different day of the week)". 
Leave the door open for the friendship with an exlicit invite to do something else, it's down to them if they want to take it, nurse their hurt feelings or let their hurt feelings fester.  Life happens, things change, friendships don't always last, sometimes they just fade, people switch jobs, have kids, move to different areas, countries etc.  Sometimes people have kids, switch jobs AND move countries and the friendship still lasts.

I like to say there are many valid ways to play D&D, and nobody is wrong, provided everyone is having fun.

This friend likes to play a perfectly valid version of D&D that isn't fun for the rest of you. Encouraging them to find their own game with people who dig that is the right way to go. It's not that they are wrong; it's that it's not a good match for the rest of you.

Regardless of the intimate details, the absence made everyone see that and you've taken the appropriate measures.

Invite them out to do non-D&D things.

You can be friends with someone and still not want them in your D&D game. Make it clear that you're not ending the friendship and let them know that you're still up for hanging out in other ways. If they are offended enough to end the friendship on their side, at least you tried and honestly you're probably better off.

What you're feeling is human. You don't want to play with the person, but you don't want to hurt their feelings either. Saying the first part is likely going to result in the second and so you're feeling conflicted. However, I think you have to ask yourself, what would happen if you allowed them to stay? What would that do to the friendship that you still have? If this ends the friendship, then is that a friendship worth having?

People play for different reasons. For some, it's because they want to be the hero and spend time with friends. For some, they use the game to work through inner demons and let out thoughts and feelings that aren't safe to release any other way. When those two play styles clash, it creates tension. Either you figure out a way to accommodate it or you agree that they don't mesh. Hopefully, your friend understands.

Quote from DoveArrow >>

What you're feeling is human. You don't want to play with the person, but you don't want to hurt their feelings either. Saying the first part is likely going to result in the second and so you're feeling conflicted. However, I think you have to ask yourself, what would happen if you allowed them to stay? What would that do to the friendship that you still have? If this ends the friendship, then is that a friendship worth having?

People play for different reasons. For some, it's because they want to be the hero and spend time with friends. For some, they use the game to work through inner demons and let out thoughts and feelings that aren't safe to release any other way. When those two play styles clash, it creates tension. Either you figure out a way to accommodate it or you agree that they don't mesh. Hopefully, your friend understands.

 Thank you, I 100% agree with you here. X's being weird about this situation, we made it clear that we do still care for them and that we wish to stay friends with them, but they vanished again, so this feeling of uneasiness about them is only growing at the moment, I hope they will understand where we came from one day.

Quote from scatterbraind >>

You can be friends with someone and still not want them in your D&D game. Make it clear that you're not ending the friendship and let them know that you're still up for hanging out in other ways. If they are offended enough to end the friendship on their side, at least you tried and honestly you're probably better off.

You can be related to someone and throw them out of your gaming group if their conduct warrants it. 

Are you happier playing the game now that Person X is no longer playing? 

The answer to that question is the answer to your question. I don't believe any other opinion of mine should matter.