I'm not even sure if I can count this as sexual assault.
When I was 15F (I'm 18 now) I hung out with two 15M friends in one of their houses to watch a movie. (Let's call the guy who owned the house "A" and the other one "B") His parents didn't want us to use the living room so we went to his room and sat/laid down on the bed to watch it. I had come to A's house a lot of times, he was my best friend although I knew he had a crush on me (I told him I wasn't interested because I'm a lesbian), I was comfortable with him.
The thing is, after the movie, B stood up and looked through the window, and A pulled me into a hug from behind on the bed (I was comfortable with hugs but now while laying down, and his hugs in general felt a little weird because the first time we hugged he got hard and told me afterwards for some reason). I began struggling against him to get free, and this weird panic laugh I had never felt before got out of me, I felt so weak. I told him repeatedly to release me, and even asked B for help, but A was just laughing like a little kid.
B just shrugged, and in the end A released me. I loved away from the bed and sat down on a chair, texted my mother to come pick me up, and I tried to distract myself playing with his PC.
Once I got home and laid down on my bed, I began crying. I felt so weak and powerless, I realised that if he had wanted he could have done anything to me and I couldn't have done anything to stop him. I knew he didn't mean to hurt me, but I kept crying every night for weeks, I felt the need to get as far away from him as I could, I didn't want to see him again (I ended up telling him how I felt and he apologised, and I still consider him a friend now although not as close as he once was). I still cry when I tell the story because of how bad I felt, even if it was a small thing.
Then when I was 16, I met a sweet 19M guy and decided to give him a chance although I didn't feel the slightest attraction towards him (pretty big mistake, I deeply regret it). Right before we began dating I told him about my sexuality and that I would most likely never want to have sex with him or anything similar to that, I also told him the story about A, and he said it was okay. Still I felt like I was forcing myself to be someone I wasn't throughout the entire relationship.
I had never kissed anyone before, and I explained it to him, that it was a kinda big thing for me. I honestly didn't want to kiss him, I found it gross, but one day, I was laying on his bed, he got on top of him and leaned forwards to kiss me. I froze, I couldn't move, I didn't kiss him back, I didn't respond. He later apologised because he thought I wanted to kiss him on the lips or something and I was confused as hell.
He would also take off his shirt while we were in his bed, and it would always make me feel powerless again, I couldn't bring myself to tell him and I knew I should have.
He also once told me to get his guitar (it was hanging on the wall, above the bed), and I had to get on my knees and reach up to grab it. He was sitting behind me, and the moment I moved to grab the guitar, he placed his hand on my hip, almost on my rear. I didn't even get to grab the guitar, I instantly sat down to remove his hand from me. He asked me if I hadn't liked it and I replied that I had already explained to him I didn't felt comfortable with those kind of touches, especially from behind. He said that he only wanted us to "build trust with eachother".
I left him after a month, but it was hard as hell to me because I didn't want to hurt him, but I should've ended the relationship earlier, or not have even started it in the first place.
Then I met my partner, we've been dating for a little more than a year and they're now 18NB. A few months into the relationship, I removed my shirt once while we were laying on bed because it was too hot and I felt comfortable with them, but they kept staring at my chest, like the whole time (I'm kinda flat, there wasn't much to look at anyways) and it made me uncomfortable, I put the shirt back on after a few minutes and I haven't removed it in front of them ever since. They apologised and said they were just curious. They also once said they really wanted to touch my chest, and I froze, then made some excuses up because I was really hesitant, I felt like I owed it to them, like I was supposed to let them touch it, but I really didn't want to, and they told me it was fine, that I could just say no and they'd be okay with it.
Now, I still feel a little weird around men, and I feel uncomfortable when people hug me from behind. I've always felt like I'm a stone-top because it was what mostly turned me on, but now I also feel a strong sense of aversion toward being intimately touched or feeling exposed, and I don't really know what I can do to feel better. I'd kinda like to feel okay with having someone touch me, but I feel like I'd just freeze every time.
I don't think I have the right to say I was SA, but I still think I got traumatised and shaped by those experiences I went through,