Here is what works for me: it's not that my thoughts that I am ugly ever completely went away, but I have always fought back when those thoughts got into my head. I argue with them, and I surround myself with images of beautiful fat people and tell myself that if I think they are beautiful then it makes sense some people think I am beautiful. And I also try to treat myself the way I would treat a close friend. I wouldn't tell a close friend that they are ugly, so I shouldn't tell myself that I am. And if someone else tells a close friend that they are ugly, I would vehemently disagree.