Again, this is just what I do, I'm not speaking for anyone else....

When I am depressed I don't vocalize that I think I am crazy. What happens when I am depressed is that I so completely hate myself I can't see how anyone can love or even like me. In the case of my gf, the one person who tries to help when I am down, I push her away just because I see myself as so worthless I can't see why she is wasting her time on me. My mind will then tell me that since I am so worthless, I am doing a favor by ignoring and pushing this person somewhere else, they will be happy in the end that I am out of their lives.

Eventually I win out on some level and get her to stop talking to me. Then a month or two goes by and I wonder why I did that, wish I had that person back, etc.