I don't think anything's wrong with you - I think it sounds like you have an objective grasp on things. Good for you, you are confident and don't feel disgusting - since you surely aren't disgusting, and it sounds like you are loved. But you realize that you're overweight. Perhaps instead of wanting to be "thin" you could try to inspire yourself to be fit, for the sake of your health? I like to read Oxygen women's fitness magazine, the pictures and articles inspire me even though I don't look as buff as them. They usually feature an article about someone who went from fat to fit in each magazine. I think the current issue is about fit moms (I haven't received my copy yet). Maybe you can exercise with your boyfriend, then you can spend time together and get in better shape. Think of the health benefits of trimming down a bit.
Hope you get things figured out!
~Squeaky