Kiki,
I won't begin to tell you the women I have seen in your position and what happens to them. You are already showing the signs of abuse. You have no self esteem and he has already convinced you that you can not do better than him. You are the classic abused and manipulated individual. Psychological abuse is just as bad or worse than physical abuse. The good news is you are young, pretty and more important you have not married him and most important do not have any kids with him.
Girl, you don't have a problem. You just need to open your eyes, listen to what every person on this board is telling you and do what you know needs to be done. Here is something that helps. Step outside of the situation and imagine you are much older and have a daughter your age that has just come to you with the exact situation you are telling us. You know what you would tell her to do and you need to have the courage to do the same thing yourself.
Go to your family and tell them what is going on in your life. They are your family and when everyone turns their back on you, they will be there. You owe them to tell them the truth. Forget men right now and fix yourself. Whether you realize it or not, you have been damaged from this relationship and it has absolutely nothing to do with any medical conditions you have. Unless you take the time to realize who you are and build up some self confidence and self esteem, you will repeat this mistake over and over.
I'm not trying to be inconsiderate, but honest with you.
Good luck to you and get your self together. You have a long life ahead of you. Make it a happy one. It's all in your hands.