I think you might want some more time to think about this.
It seems to me that you have outed her behaviour - and no-one likes you rocking the boat, except you, because you are the only sane one there....
While you stand so close to them and their viewpoint, it will be hard to keeo sight of your own.
I think you wanted her to make it good when you told her where you were coming from and asked if she was able to hear you....
The mistake, or the humanity, of that position, is that if she could hear where you were coming from, she most likely wouldn't have been like she is in the first place.
But she is, fact.
I remember going through this myself with my folks. It took ages for me to understand that they weren't going to change, and they were going to be angry with me for not being OK with how they were....
But fact, I was not OK with it.
I think she has made herself very clear here - do as I say or I will abandon you - and I think that in time, sad as it undoubtedly is, you will feel better in other ways that are not to do with the sadness.
I have been about 15 years away from my mother, and about 6 years from the rest of my family, who chose her over me. It gets a lot easier.
But today might suck. So take care where you can and sorry and well done for standing your ground.