How do i do substances/substance abuse in D&D?

I dug out my old rules for addiction which I thought were quite effective without telling the players how to act:

The premise I went for was that a character would be at disadvantage (I.E. one point of exhaustion) if they were addicted but hadn't taken their addiction today. If you go cold turkey, you can break the addiction, but whilst doing so you will be exhausted. As soon as you take the addiction, the exhaustion goes away. Thus, the character is inclined to drink the addictive drink, the player can see the benefits of drinking the addictive drink, but they will still be addicted.

I didn't make it any more punishing than this because I wanted to keep it simple.

Please note that these rules alone were enough to make one of my players, who had suffered with addiction, extremely uncomfortable, and led to a situation where two of the characters conspired to destroy the property of another (the addiction was to a spider's venom which gave +2 to strength when bitten, one of the characters had kept this spider all campaign, and then one of the others became addicted, stole it, and then another character persuaded them to crush the spider to be free of the addiction. This led to a sizeable IRL confrontation, as the player who had kept the spider was furious at the situation and at having lost her pet.

Addiction has capacity to lead to the sort of roleplay which doesn't add to the game for everyone.