Ex assaulted me I think?

TW: assault

Basically he always always pressured me to do things I wasn’t comfortable with or ready to yet. He also was pretty dismissive of me sometimes. There was one night in particular that I remember when I felt really uncomfortable and actually kind of scared.

I walked from the living room to the kitchen and slapped my ass cause I was being sassy. Next thing I know he’s behind me pulling my pants and underwear down. I tried to pull them back up and told him not now and he kept pulling them down even though I told him to stop and tried to push him off me (he’s 6’3” and twice my weight). I finally just stopped fighting and kind of let him do whatever. I don’t really remember what happened after that, but then he pushed me in the floor with my face against the floor and humped me from behind and choked me. I couldn’t tell him then that I wanted him to stop because he was on top of me and he was choking me too hard so I couldn’t talk or breathe very well.

That’s the night I keep thinking about, but there were other times when I felt uncomfortable/forced. I guess I feel weird about it because I have an emotionally abusive relationship with my mom and because he was my first kiss and everything. Honestly I didn’t know I could kiss someone or do something sexual with someone and not feel a little ashamed or upset afterwards until a few weeks ago.

I’m not exactly sure how to help myself now. I want to feel more confident in myself, and I don’t want this to continue into future relationships. Advice? Help?