Originally Posted by kane

I think the idea is that, as he says, he feels he destroys everything he touches. He blames himself for Deb's death and the deaths of other people in his life. He feels that because of this eventually he will destroy Harrison and Hannah's lives and it is better that he abandon them.

He doesn't just kill himself because his drive to survive is too big, but now he finds himself alone, without his family or friends and, in a way, isolated like a prisoner so while he doesn't get caught and end up in jail he is still in a prison of sorts that he has created for himself.