Thanks @NatureLover
Yeah I've tried therapy time and time again and, for whatever reason, it just doesn't work for me.
I don't think I have any childhood trauma in that form. Certainly I was bullied very badly in school, but no one told me I was "bad", especially not my parents who were very supportive.
Actually, writing this right now made me think of something: The school I went to was a very small, very high-performing private school. The kids there were all very bright. Though I got good grades compared to all other students in the state, I was always at the lower end of the spectrum in my immediate class. This combined with always being psychologically bullied (as I said, the kids were very smart - they knew how to get in your head and mess you up) meant I always felt inferior, stupider and more socially backward then everyone else. Maybe that's part of the reason why.