I was abused by my sister. It was for a shorter time than you, but I experience the same kinds of feelings that you do. I am turned on by her memory, and I am ashamed that I have these feelings.
I am so sorry you have to feel this way. Seeing another's pain helps me to understand that it is not my fault; I hope you are realizing that this is NOT your fault. By acknowledging what has happened, you are taking the first steps toward repairing the damage inflicted upon you.
I do not know what else to say, because I am fighting the same battle as you. Just know that another has a similar experience, and I wish you the best.
And let the darkness fear our light.