What do i do?

**For privacy purposes, all names are changed**

So i’ve been friends with my best friend/sister, Monica*, for a couple years now. We are super close. Well she had a New Years party at her house and it was just close friends and then a couple people. Monica has a boyfriend, Cameron*, and he is like an older brother to me. Well Monica and Cameron have a baby together, and i consider him to be my nephew. Well on New Years i got super drunk, and some of my friends were taking care of me and making sure i got to bed and got my makeup off, etc. Once everyone left i was on the couch and Cameron came downstairs. He asked me if i wanted a threesome with him and Monica. Mind me, i was still super drunk and half asleep. I said it was up to her and then he said okay and went up stairs, saying he would be back down soon. I had dozed off and while my memory is pretty fuzzy, i do remember him coming back downstairs. He came and asked a bunch of sexual questions or comments. He asked if i was shaved, asked me to look and see if he was bigger than my ex (who is his friend and who i’m currently still trying to work out problems with so we can get back together). I kept saying no, and that i wouldn’t do that to Monica, but i did answer the question and say no, that i wasn’t shaved. So he asked me to come help look in the living room for a pacifier. Of course, i said okay, not thinking anything of it. I was sleeping so i said okay, but i just stayed there falling back asleep until he came back in the room and told me to come again. I finally got up, barely walking with my eyes opening, and went to help. I don’t remember if i sat down or if he sat me down, but next thing i know i’m on a couch on my knees with him pushing himself in me. I just stayed there falling asleep, but still kind of registering what was happening. Well he finally got me up and pulled out, and asked me “what did you do tonight” “did you have sex with Jake*?” Of course i said no, and thought it was weird he was asking me these questions. Well he walked me to the other room and laid me down on the couch i was sleeping on and left me there and went upstairs. I fell asleep instantly. The next morning i was hungover and thought it was just a dream, then i remembered clearly and... i’m just in shock.

Honestly, i feel like i’m partially to blame. I could have tried to fight harder. I could have said no. I felt so safe there and now i don’t know what to do. I want to act like everything is normal, act like it never happened, and let him think i din’t remember it ever happening. However, at the same time... i want Monica to know the truth. I want her to know what he did to me, but i’m so scared she will blame me. I’m so scared that we won’t be friends anymore. I want Cameron to be apart of his sons life, because he is a great dad... but i just don’t know what to do.

What do i do?