That's awful that you were forced to report it when you didn't want to.
Your friends shouldn't have done that to you! That's outrageous.
As for the actual assault, the drunkenness is what creates a gray area that makes sexual assault difficult to prove. With freedom (to have sex) comes responsibility. Sorry if I sound harsh, but I'm trying to help you put this behind you.
When I was 21, I went to a bowling alley/bar with two girlfriends. I had three shots of Tequila which made me drunk. I met a guy outside when I went to smoke. We talked and walked. When we got the parking lot, we fooled around. I felt something entering my privates and I said no I'm still a virgin. He said don't worry that's just my finger. My friend came out screaming what the fuck is this! He said he was just fingering me. She said no SG that wasn't his finger. You were raped.
So I did what an obedient member of society does and reported it. I told the truth, that I was drunk, wearing a short skirt, and that we had fooled around first. Two weeks later, the police cursed me out, saying they didn't believe me. They said I was just lying and saying I was raped to save face in front of my girlfriends so they wouldn't think I was a slut for having sex in public. I would never feel the need to cry rape to save face! I was devastated. The cop kept saying that in the real world, that's what it looks like. Ever since then, I've been at odds with the real world.
Looking back on it with help from a sexual assault counselor and some of my research, I realize I was part of the date rape craze. I wasn't raped or sexually assaulted. I got drunk, so I should have assumed responsibility and not sent out mixed signals. Sexual freedom is a gift that can't be abused.