The circumstances are just a small part of my point though. Most people are exposed to drugs and alcohol growing up and let's say half of them partake to some degree. 95% of the ones that do can maintain a life, go to school, work, have relationships but 5% of them can't deal. Those are the addicts. Those are the ones where drugs and booze consume them and they have no power over it. It's part of their DNA...
So the circumstances, yes, for sure, they're a big part of it. But the predisposition for addiction is the larger part imo...
No sympathy for drug addicts here. Drug addicts only become addicts by trying drugs in the first place.
For our entire childhood, school, teachers, the government, adults, teach us not to stick the needle in our arms or smoke the crap pipe. It's preached to us. Addicts ignore this and do it anyway. That's why they become addicts.