You may be projecting compassion and empathy that she is not actually capable of providing.
You cannot control someone else's behavior, at least not in any healthy manner. As others have already suggested, and you have already done, cut communications down to essential and required statements only. Try to use text or email if you can, and look at anything you write and see if there are pieces of it you can cut out so that you say as little as possible. Accept that she can say or do whatever she desires. If she's not getting help, or you're quite sure you are done with it, then your new goal is to get away from it, not defend yourself or expect that she will develop empathy suddenly.
I like listening to this song when I need a buffer from selfish behavior by my STBX:
https://www.youtube.com/watch?v=C6PNc9KN50M
Here's a book I found about the divorcing a narcissist, and it has good reviews:
https://www.amazon.com/Divorcing-Narcissist-One-Moms-Battle/dp/0615720552