Sucking Out the Poison

On January 5, 2018 I was sodomized by my boyfriend at the time. It was during one of our parties. He came into the room during the middle of the party, raped me and then he left the room. He came back in after he realized that everyone left and started yelling at me, telling me everything that was wrong with me. He broke up with me after that.
I think this was a hard fact for me to admit, even to myself. I kept denying in my head that he raped me because surely you can't get raped by someone you're in a relationship with, right? But that was so wrong. I should have done something about it when I had the chance but I played on denial. The hard truth is: I asked him to stop repeatedly, I told him no repeatedly, I tried crawling away from him and he just kept going. I was raped, no matter how I try to deny it, no matter how I try to downplay it.
Why is it coming out right now? He's recently starting dating the man that he cheated on me with and I was incredibly angry about this. My sister pointed out that I can't keep holding on to all this anger that I have, that I need to let it go. I think the reason I have so much anger and hatred towards him is because he doesn't deserve to be happy, not after what he did to me. He's a fucking rapist for crying out loud. It's almost become an obsession with me, hoping to see that he's doing awful because I want him to have such a shitty life. And I'm so incredibly worried that he will do it again to someone else.
So, I'm going to go see a therapist and see if I can get some tips on getting through the trauma. I am also going to block him from Facebook so I no longer have the temptation to creep on him. I told my friends that I don't want to hear anything about him. From this point on, he is dead to me.
Unfortunately, I don't really think that going to the cops at this point would do anything, other than create hella problems for me. At this point, I have no proof that this happened and I'm assuming that means he would need to confess. I promise he's not going to do that. So, all I can imagine is that if I go to the police, he will find out and come in and take everything that he left at the house for my roommate and I to use. Yes, that stuff is easily replaceable, however I am no where near able to spend that kind of money on new stuff. But I really, really don't want him to do this to anyone else. So, I'm going to write him a letter telling him exactly what he did to me and letting him know how it fucked me up. Maybe if he sees what he did to me and how it affected me, he will stop himself from doing it again.