How to deal with Ace-erasers?

I was unfortunate to be on the receiving end of someone's abuse who was transgender (Male to female), self-identified as a radfem, and let slip that she was diagnosed with Histrionic personality disorder.

She threw me under the bus to sell her position that "all men are pigs" via slander and libel that I don't have the funds to hire an attorney to recoup damages over, long story short I was accused of looking at her breasts and when I mentioned that such was nonsense and that I am asexual and don't even experience sexual attraction let alone have a breast fetish, she did everything she could to discredit my asexuality and even go as far as to say that asexuals didn't exist. I then made the mistake of seeing her lack of remorse for her conduct and remarks and lack of ability to empathize as an indication that she needed to feel through other means, so I then pretended to not acknowledge her identity to show her how it felt, now she's still selling her original claim but now she is also using screenprints of that very little snippet of said conversation to try and claim that I am transphobic and doing everything she can to silence me. All through high school I was bullied when it got out that I found large breasts to be repulsive and did not find breasts to be attractive (There was an incident where a large breasted girl tripped and planted her breasts in my face while I was sitting in the hallway, and I freaked out to where people could clearly see that I was grossed out, this lead to people first interrogating me then bullying me over how I replied to said interrogations).

How do I deal with this kind of abuse and what could I have done differently?