I lived with alcoholism and drug abuse from age 14 to age 24, and it almost completely destroyed my life. Now I only drink like four times a year at most, and stopped using hard drugs around 2015. Whenever I drink now, I hardly can have more than some cups of wine or some cans of beer and I already just wanna go to bed. The next day, I always feel like dogshit and decide to take a long break, and then I legitimately do.
It might be dumb, but this intolerance to alcohol makes me extremely happy. I think being able to take ridiculous amounts of alcohol and drugs, and then feel alright the next day, was the kind of impunity that only made my alcoholism, drug abuse and depression get worse and worse through the years. It didn't help that many of my friends in that decade were alcoholics and drug users too, some of them still being addicted to this day, which made me think this was the only way to go about things, and that it was normal to have one, two days of debauchery if not more every week.
I do believe that what people say about addiction is true: if you have other things in your life you actually care about/for, you won't completely stop consuming alcohol, drugs or whatever, but you will certainly consume way less than if you had nothing but drugs and alcohol to pass the time. I went from not giving a shit about what happened to me to actually feeling morally obligated to be alive and healthy, because I have a home, a husband, a cat, an artistic legacy to work for, things i care about and that are worth being alive for. it certainly helps to have worked for a body and mind i actually like, things i'd rather not sabotage anymore.
now, i bet i could tell anyone about my actual consumption levels and be told i'm just a baby, that my consumption was minor enough that i shouldn't be so overly dramatic about it, but iunno dude, i was there to see the damage i caused myself and others while drunk or high, and i'd rather not live like that. i'm sure other people can take a little bit of this or that and be perfectly fine and worry free the next day, and i'm sure that those people might actually have nothing to worry about, but that wasn't me.