I think his father exploited him by writing that book. He was counting chickens that hadn't hatched yet, and one wonders just how much money drove the father. I think he heaped a whole big pile of expectations on his son, made a bunch of dough off of him, and ultimately made it so that if he wasn't the next Bobby Fischer, he was a failure.
That said, I have no idea what was going on inside the family, so I'm speaking from a position of very limited information.
This is a very sad story.