I was raped by my step brother, what should I do?

I am 15 years old right now and my step brother is moved out and 19 years old. When I was younger my baby sitter's husband used to give me money so he could finger me. I was about 9 when I stopped needing a babysitter, I don't remember how young I was when he started doing it. I was 7 or 8 when he stopped though. I never told anyone. I don't remember how young I was when my step brother started raping me. He would come into my room when no one was home but us and he would tell me to do things to him and he would put himself in me both in my mouth and private. He also would touch me. He always told me that what he did was okay and when I got a bit older (around 10 or 11) I told him I wanted him to stop. It was the scariest thing ever to tell him that. It took everything I had just to say that. At least two or three times a week he would come into my room before I said that. After I said it he would only come into my room every other week and would always say that this would be the last time and he would promise me. When I was around eleven or twelve it happened less and less until he finally stopped. He always treated me like everyone else and would act like nothing happened but then he would come to my room when we were alone. I always tried to find excuses to get away when he was doing stuff to me. He is 19 now and we don't really talk. After he stopped he never said anything about it to me and acts like it never happened. My stepmom hates me and there is no way I would ever be able to tell anyone. I am fine with him now and also act like it never happened. I still can't help but feel horrible about it though, like I should have told him no with more force. I can't sustain a good relationship with any guy now and sometimes find it hard to trust them or let them touch me besides hugs. This the first time I have ever said anything outside of my own thoughts. I don't think I will ever tell anyone I know about what I just wrote but someone needed to know. It feels like a load has been lifted off my shoulders. I don't blame him that much any more. He has a girlfriend and they have been dating for almost 3 years. He has moved on and I am on my way there. I just want to thank anyone who read this. Everything I wrote has been completely true so please don't leave any mean comments. If you want to leave a nice comment though you are definitely welcome to. Thank you so much.