I mean we really have only your version, but it just seems like the classic manipulation tactics that narc, or any other shitty people use. My mother was a real narc and everytime someone did the most tiny "bad" thing, it was overdramatized and exagerated.
You're not an abuser because you punched your boyfriend n the face when he invited a fucking girl over. Him fucking choking you? That's abuse. When a girl punch a guy, usually he can gets hurt, but not much. When a guy choke a girl, she can fucking die.
What do you do about it? Well I don't really know, I never lived in a city when it mattered that someone could smear your name. For your "friends" (that aren't really your friend if they don't even ask for your version, and mostly stupid too when most abusers are men) I would just clarify the situation and explain it plainly, with all the dirty fact. Especially the "he invinted a girl to fuck her when we were together, and he choked me on the ground"
If they still thinks he's the abuser after that, they made their choice, and they're just shitty friends. Good riddance I say