My [18 M] cousin [21 F] physically attacked me at Thanksgiving dinner and my family is offended that I won't accept her apology or visit again until she leaves.

It's worth noting that I'm a very short (five three), skinny and effeminate guy. I am gay and while I'm not 100% out of the closet everyone already knows/assumes by my voice, which is something I can't really control.
I don't see my cousin often. She lives with my parents while going to college and I visited my home for Thanksgiving (I go to college out of state) and saw her with the rest of my family. She is very tall for a woman and is a college athlete with at least forty pounds on me. I know she is conservative and she has made multiple "jokes" at my expense at the past to my face regarding my sexuality, which I've always ignored.
This Thanksgiving dinner she was loudly making fun of the fact that I was helping to cook (I was the only man doing so). Everyone else is my family (save for her parents who we are all estranged from mainly due to drug use) is left-leaning and doesn't support her "jokes" or attitude but never speaks up to criticize her. Her parents were extreme conservatives and treated her very poorly growing up and this is often used as a defense of her behavior by my family who says that we should understand her circumstances. This really means that I have to "understand" it because I'm the only target of her behavior. They never speak up and I've learned to suck it up because I don't see her that often. My mother and father grew up in extreme poverty themselves (we are now safety middle class) and have a lot of sympathy for her and tend to ask a lot of me with dealing with her because of this.
She had been making fun of me for ten minutes while I was helping to finish up the final preparations and bringing the dishes to the table. This was in front of everyone, over ten people all who supposedly don't believe in the same things and nobody said anything. She said the F word three times while I was bringing out food which she hasn't done before (openly to my face).
While bringing the food I accidentally dropped the cranberry sauce on the part of the table and what might have been a tablespoon's worth of cranberry sauce landed on her shirt. Everyone agreed that it was clearly an accident after the fact, but she didn't believe it, ignored my sincere apologies, stood up and said I was being a coward and rapidly slapped me hard across the face twice before shoving me HARD against the wall. I have multiple small bruises on my back and my left shoulder from this.
My dad stepped in between her after she made it clear that she was going to continue but the issue was "deescalated" and everyone asked that we continue dinner. My cousin jokingly apologized "Sorry you're so clumsy!" and they basically started to eat almost immediately after.
I left the room in tears after a brief minute of disbelief and drove back to school without saying goodbye to anyone. I got sympathetic texts from my mom who despite taking my side officially continued to defend her and an uncle + aunt of mine told me i was being extremely dramatic and I've gotten call after call (six in total) from adult relatives who expect that I be okay with what happened and that I need to understand her history. My cousin ended up only yesterday sending me a paragraph text of an apology that is better but basically still blames me.
I know this seems easy but i have a room full of people who taught me right and wrong calling me and saying that I need to accept this and that it's the way it is with her and that she'll get better "over time". I finally told my mom that I won't ever visit home with her still living there and she got MAD at me and told me I didn't know what going without eating was like.
I haven't lived in poverty but I'm not a spoiled brat (parents combined income was 75000 a year, I'm paying for my own college and going into debt with no help from them, have had a job since 15) and I feel they are treating me like I am because I don't want to be around a person who physically attacked me probably only because I'm gay. I feel delusional and I know it's a word that gets used a lot but I think I'm being gaslit very badly and I really want to make sure that I am.
I'm being reasonable right? I'm not saying that I should have zero sympathy but she needs to NOT ATTACK ME on thanksgiving?
TL;DR: My cousin physically attacked me at thanksgiving and is regularly homophobic to me. Parents (who she lives with) and family asks me to deal with it because she came from a terrible home and are mad at me for making an ultimatum that I won't come home until she's gone.


Source.