hi mistreatedmisfit,
Welcome and I think you will find a lot of support here, we get it.
A couple questions, do you have siblings?
It is good you realized you need to take care of your own emotional well-being, that takes courage and shows a lot of strength. It is OK to ask for help, afterall, how can we solve a problem we really know nothing about?
What is your next step now that discussing it with her doesn't seem to be working? What kind of boundary do you feel might be appropriate now that you've exhausted the "working it out in a reasonable fashion by talking about my feelings' didn't seem to help.

b