Exactly. I always thought of myself as responsible and healthy (and I basically was). I never overused alcohol, never binge-drank etc. I absolutely had no understanding how people could not regulate drug use because I had no problem with it.

A few years ago I had a lot of stress and started drinking to help me sleep. After only a few months I felt kind of agitated without a nightcap. I immediately stopped and now I just don't drink when I'm stressed.

So maybe in one sense I was right about being responsible, but on the other hand it could have very easily become a habit and now I understand how people slowly slide into addiction. It's arrogant to assume anyone knows how they'll respond to a drug as habit forming as heroin.