I know we discussed this in chat last night, and I too feel the "bad"ness. I know it is, in part, from not being validated and accepted when I was a child. The child in me concluded that there is something horribly wrong with me. If anyone gives me a compliment I automatically dispute it, if at least only in my head. I guess I get caught up in the punishment of beating myself up. I logically "know" that I have not done something so horrible as to forever label me as bad, but I just can't rid myself of that feeling. It also goes along with abandonment issues, that I am sure people will find out the "real, bad" me and then they will leave. I even went throught this with my therapist, almost trying to "prove" that she would leave me. I still can't completely shake the feeling that I will be abandoned, by anyone at anytime. I could not handle that much disappointment and so I try to beat them to it by putting myself down. It's almost easier if I assume that I will be left alone than to take the risk and depend on someone and really be hurt when they do.
I know I am rambling. This really hits on my core issues. I am trying to let you know that I understand how you feel. I am trying to work on it, but I am just not there yet. Good luck to you. HUGS!