While there are definitely some tortured genius types out there, I think many of those who present as such described in the article really aren't. You know, it's pretty easy to appear like a genius when none of your peers have anything to show for it either. The only question I ask for genius is "What has this guy done?". Which is a pretty difficult question to answer when you're still at school and haven't lived a life yet.
Our own self concept is based on the story we tell ourselves. This is an important emotional/intellectual regulatory tool we deal with in a daily basis. Evolution gave us self reflection because it's very useful to us. But it doesn't mean it's a reflection of reality.