Why did Nietzsche became insane?

Question:

Why did Nietzsche became insane?

I heard that he was madly in love with her sister, and her dismis put him on the way to the insanity, but I cant find any referenses of this on his biographys (altough the may insunate something alike)
Any toughs?

Best Answer - Chosen by Asker: One of the reasons is, according to a book by Alain de Botton (The Consolations of Philosophy), he was obssessive with his complex thoughts till he visualized himself as the Buddha, Jesus Christ, etc. that is, great people in history. In other words, he went too far in the field till he lost his fine threads of consciousness into the unthinkable dimension no one could understand him, it's a pity indeed. I respect his brilliance but how we should help or prevent anyone with his/her simmilar syndrome is, I think, a challenging question.