Cheating?

So in November I went to a party after a football game without my boyfriend of 2 years. And my friends brother had sex with me.

For context, it’s important to know that I had 3 major shoulder surgeries alone in that year. I was severely depressed and suicidal so going to this party was an awakening for me (I thought). My doc put me on Zoloft and I took my meds that night and drank a lot of alcohol. I didn’t realize the danger I put myself in by doing that until about a week later when my head still wasn’t right.

After drinking a lot, I was walked back over to my friends house and her brother and I were left alone. He tried making advances on me and I pulled away because I was tired and I could only think of my boyfriend. He kept going and I was scared. I felt I sobered up a tiny bit but not enough. I remember hurting a lot because of the surgery I had only being 2 months prior. My body froze. However I don’t believe this was rape or sexual assault because I didn’t say “no” or “stop”. My intentions weren’t to cheat on my boyfriend and I did try to get the guy to stop. I am confused.

Yesterday I felt an overwhelming feeling of guilt that I had to tell him because he always asked what happened to me that night and I didn’t remember for a while but it really cleared up in December and January. I told him yesterday about what happened and he called me a cheater. He broke up with me.

I hurt so badly. Idk what to do because we’ve been together for a really long time and I hurt him but I was also hurt. I need suggestions so badly.