With myself and everyone I've known like me, it's definitely not self inflicted. I got the perfect storm for instability: Both of my parents are severely mentally unstable, my childhood was filled with abuse and neglect, etc.
But the crazy didn't really start for me until puberty. It was instantaneous and permanent. I went from a kid that just wanted to play, that was a bit shy, to a shut in overnight. Never wanted to leave the house. Felt like everything I touched was contaminated. Went from a kid that liked to go out and play and get dirty to someone that had to take multiple showers every day, wash their hands until they bled, was paranoid to touch anything in a public place because of germs. Overnight, with no history of giving a single fuck about things like that.
Then came the anxiety, and severe depression. By my late teens I was thinking about suicide every day and harming myself. Drinking until I'd black out, etc. It was horrifying. At a time you're supposed to be trying to establish an adult self, my mind had been taken from me by forces beyond my control. I'm a lot more stable now, and I've worked goddamn hard to GET more stable.
But I'm not normal and I'm not happy. I struggle to date or make friends, to work a job without eventually losing my temper and ruining it. I think about killing myself every single day. I'll let my mind wander then realize I'm debating the merits of hanging vs overdosing vs driving my car off of a cliff. But I go on and I make plans and I say around the corner it will get better. Although it never does. And then I look at someone that just couldn't do it anymore, and all I feel is sad for them. Even if they had more money and friends than me, women flocked to them, whatever.
Obviously whatever they had still wasn't enough to beat the sickness every single day. And you're in a battle every day and you HAVE to win every day. Then someday you just can't anymore and people say what a pussy, he should have tried fighting it.