Because everyone is dead.

[ He's not sure if he screamed that or cried it. He's certainly crying now. ]

It wasn't failure, it was me. My parents died because of me. My people suffered because of me. It does not matter how caused the final blow, it was my hand that led them there. And I cannot do it again. I cannot pretend that I am going to be better anymore. I can't pretend that. I can't lie about that.