Should I just end it all??

first thing first,she's not your friend. Why does she always bring up that the fact you are gay. Friends don't do that and the fact you have told her about it and she still does it. I think she is jealous that you have more friends than her and you seemed to be like by more people like than her. You don't need a person who talks down to you and there is nothing wrong with being gay and that's cruel. I would stop talking to her and when she says that she will change. say nothing, Don't answer the phone don't sit with her. This will make her understand that what she is doing hurts you. personally for me i would never speak to her again. sorry for your stress