The guy is a bit of a snowflake. He claimed to have read Dostoevsky and fell into a pronounced depression from which it was difficult to emerge. But I don't believe it for a second. I think he is just trying to convince others that his intellect and understanding of the human condition and human suffering is so deep that he can't detach himself from all of human suffering.
Wouldn't surprise me, to be honest. Dostoevsky himself was prone to reacting very strongly to situations that probably came off as mundane to others. That's why he has written a lot of his characters to be rather melodramatic, exaggerated in their behaviour and responses.
The idea of suddenly falling ill or having a seizure over an "epiphany" is pretty distant to most people. But not necessarily to people like Dostoevsky, and I assume Peterson as well.
That's why I think that he has actually had his shit together pretty well, mentally, considering that his physical constitution is not necessarily fit for any kind of public work. When you're allergic to basically everything, have problems with your immunity, burdened with a family history of addiction, depression and anxiety, it's just a different path to take from most everybody else's.
The way I see it, he has been the perfect representative to preach to the future generations of men, which are bound to suffer more from anxieties, depression, impotence, hyper-sensitivity, lack of identity or meaning, than our generations have. As someone who was not necessarily blessed with a strong physical constitution, Peterson did fairly well for himself, and carved out a place for himself in the world, a family, a well-paying job, and a position of prestige in society. Thus, he is in a better position to talk to the youth, than the "old bulls" to whom "toughing it out" and "manning up" came as naturally as breathing.
To some, he comes off as too weak or meek, but he's not really trying to motivate a group of UFC fighters for a cage match. He's trying to motivate some people to come out of their shell and live a life.