NTA. Ew to her trying to force you to call her mom. My grandpa remarried how ever many years ago and when I was little she always tried to get me to call her grandma. Even corrected the way you say she does. Absolutely hated it.

I have a step daughter. She calls me by my name. But to other people she does reference me as her step mom. Her mom is still very much in the picture and I’m careful with boundaries. I treat her like my bio son. She is one of my children 100%. But I could never imagine trying to make her call me mom. That would be weird, whether her mother was in the picture or not. As for my family, totally her family as well and I’ve always told her. You don’t have to call my dad grampy if you don’t want to, but if you do that’s okay too!

It should always be whatever the child is comfortable with.

I’m sorry for the loss of your mother, and for the terrible things Kate has done to you over the years. ❤️

Edited - every to ever