[Eternal]

You should talk to your mother about this. Tell her how much it upsets you when she calls you fat, and how much it affects you. As your mother, she should be supporting you and making sure you have self-esteem rather than break you down.
Try your best to ignore her, you're beautiful. Whats important is if you think that. Don't let her words change the way you see yourself.
Instead of starving yourself and throwing up, just eat healthy and get some exercise. You'll still stay at a healthy weight, but it will be better for you and keep your metabolism up.