You might not be able to change how your father behaves, but you can change your own attitude and, in turn, change him a little.
When he calls you names, ask him 'Would you like people to speak to you like that?' Sometimes say things like, 'Look in the mirror, dad' when he tells you you're angry, or "If I were happy at home, perhaps I wouldn't be," when he calls you a b*tch.
I honestly think you should approach your father with an attitude of sport or a challenge, and make replying to him kind of fun for you. Don't let him depress you, and don't consider extreme measures to try and look 'pretty.' Instead, start building your confidence by standing up to your father. Not in fights, but with words.
So when he laughs inappropriately, say "That's not funny, dad. By your age, I thought you'd understand that."
Or, "You're the only one who is laughing. Can't you see how cruel you are?" Sometimes fathers need the obvious pointed out to them. So try pulling him up every time he makes you feel self-conscious. Tell him if he encouraged you, you'd be more likely to be able to lose weight. 'Meanwhile, I spend too much effort just trying to get through the day putting up with your rudeness.'
As his behavior improves, start having some fun together. You don't want to remain battling with him longer than necessary.