I cannot add any more to the excellent advice, but I just wanted to say how sorry I was to hear this.
In a way I can understand why you don't want to leave - I think if it happened to me my first reaction would be to want to forget about it and go back to the time before it happened, because otherwise this changes absolutely everything.
The trouble is, it already has changed everything and it is not your fault. You did not make this happen and yet you are now faced with this horrible decision. Please be strong though.
This happened to my sister and she thought it would only happen once. It didn't. People who do this share similar traits and one is to make their victims feel like they somehow "asked" for it and therefore if the victim changes their behaviour it won't happen again. But you have to believe that this is not the case and if you leave it then there is a very big chance that it will happen again and your self-esteem will be slowly eroded. You cannot live your life like this. You deserve a lot better than this.
I really send heartfelt sympathy for the situation you now find yourself in. I really hope you can find a way through it.