NC means No Contact.
Thank you Chipper Monkey, I agree with the whole not-forgiving if someone isn't sorry. I also agree that forgiveness should be for yourself and not the other person but, when someone is just totally not sorry (and in my mother's case, shifts the blame onto me) so not only is she not sorry, she thinks I'm at fault....
yeah I just can't forgive her right now...if I forgive her it would almost feel like a betrayal for me, like a get-out-of-jail-free card for her.
I don't have any contact with her right now. I've gone years without speaking to her, and it's been about 3 months since the last time we spoke. It doesn't bother me, my life feels better without having to listen to her twisted way of thinking.

I do worry if I'll ever need to call her in case of emergencies or needing some sort of advice financially or whatever else...the thought of ever calling her asking for help just makes me want to throw up...because she soaks that up and throws it back in my face like "See, you DO need me, you can't be successful without me in your life!" and I can just imagine that narcissistic smirk that she would often have whenever she was being condescending.

Edit - I have had countless conversations with her, I've tried every technique imaginable, from being as calm and polite as possible, to being very direct and matter-of-fact with her. It's always the same outcome no matter what - she denies, denies, denies. It ends up becoming a screaming match or until one of us hangs up on the other. One time I was crying on the phone to her, and I heard silence on the other end so I thought she was finally listening, but I realized she had hung up already and didn't hear anything I was saying. Her ability to deny and switch things around is phenomenal.

Her favorite phrase to use in these conversations is, "I don't remember that ever happening." or "You're lying!" or "I never did that."
It makes me question my own sanity - which is a technique narcissists use called "Gaslighting".

And because I would often fight back against her abuse, she says I was a "brat". A brat for standing up to her abuse. One time I made the mistake of sarcastically saying "Gee, I'm sorry I was a brat" and she said "That's a step forward, thank you." It made my blood boil. She basically tricked me into apologizing when she never once apologized to me.
She will also say, "I have apologized to you." and I'll search my memory for a time when she ever apologized, I can't find it. I guess it's easier for her to say she already apologized without actually having to apologize.