Is she being abusive after i became a submissive bottom to my Pre Op Trans Girlfriend?

Hey Everyone i am dating my beautiful Pre Op 42F Girlfriend as a 19M Straight Guy. Initially i was the dominant partner and her being submissive but now after few months of kinky intimacy it’s become the other way around where i am regularly being railed as a bottom and dominated by her. She no longer wants to be submissive towards me as she enjoys dominating me more and topping me. She explained that since my penis is much smaller than hers , ( mine is 5 inches while she is 9.5 inches ) i don’t have the ability to please her and should be her submissive lover instead and always bottom for her no matter what. Although i do enjoy being a bottom for i really wished we could switch but she wont listen.

Even today i was bent over and fucked relentlessly and spat on by her. She tells me im nothing but her personal bitch as she fucks me. I still love her but don’t understand what to do.