Best friend dating my sexual abuser

So my best friend and my cousin who sexually abused me for 6 years are dating. And my heart is just broken. My best friend knew of everything he did to me, and even cried with me about it. And then all of a sudden she’s dating him and has barely spoken to me since. So I tried to communicate how I was feeling in the nicest way possible, telling her that all I want is her to understand my side and also that I feel like he is all of a sudden more important to her than me. And she has not taken it well and is totally missing my point. I don’t know if I’m wrong or right but I’m just broken. I feel like after everything I told her she is just throwing it back in my face like it’s a joke.

Should I just give up and let her go or what? She was like a sister to me