I dont have alot of time to put in a lengthy response for you, but my biggest piece of advice for you is to focus on what you do like about yourself, rather than what you do not like. Even if its something small, like the color of your eyes, or whatever. Focus on something positive and you will start to see your beauty.

You may also look into daily affirmations, which i have just learned about myself. The idea is to repeat a phrase to yourself when you get up to start off the day with a positive outlook on the issue at hand. Perhaps adapt this to standing infront of a mirror and finding a new aspect you find beautiful about yourself each morning.

And dont forget, that your appearance doesnt count for anything. Internal beauty is whats most important.

Best of luck to you