"She has cheated on me twice before, but I loved her so much I couldn't let go."
My dog jumped on the table to eat a cake I had made, so I made another cake and left the dog alone in the room again. I just came back and it had eaten the 2nd cake, but I'll just make another one and then leave the room again.
I don't want to sound mean, but don't let her just walk all over you and possibly give you an std in the future.