Hithere
That message is awful
Cut her off. Today. Now.
She may want you to chase her "no mommy, please talk to me"
Wait for some time to see if she is going to contact you again
My own narc mother told me the same nonsense, especially:
When you are a mother you will understand
I tried my best
Etc
The message is confusing but I feel like there are some positives, she clearly is saying that she loves you and thinks that you are a beautiful person, she is I think saying that her parents made mistakes but that she doesn't feel that cutting them out of her life is necessary. She hasn't addressed the abuse, or said what it is, and we don't have information on what was said before or after that email so I feel like there are lots of gaps here.
I don't like the way that she says that your behaviour is toxic, I don't though know what she means by that. I definitely think that if you feel that you haven't been heard you could leave the door open and give her the name of a therapist, or family therapist that she could arrange to see and invite you if she feels she wants to own some of this mess in the future.
Alternatively, if other members of the family are also not speaking to you, what about sending an open letter explaining the situation as you see it, why you don't feel it is possible at the moment to have a relationship with your mother, that you understand that this decision might not be welcome by other people in the family but nonetheless it is your decision, alongside your reasons. That you are happy to have contact with them (if you are), have a purge if you feel it is going to help you?