What you've just described is exactly how i feel. I don't know if this will help at all, i was talking to my mam about how awful i feel about myself, and she told me to pick one thing, just one, about my body that i actually liked. Took me a while, but i finally picked my eyes. Then she said that every time i start toget depressed over the way i look and stuff, just say to myself "but i like my eyes." it's not much, but it is a start. And think about it, if all these people are saying you're pretty then I doubt they're lying, or just saying it to be polite.