Hi Stosh-
And welcome! I'm sorry you're going through that, all that work, rehab, commitment, and she doesn't want it, very painful and confusing. There is a way out though, which includes grieving the loss of the relationship, processing all the emotions, and seeing what we can learn about ourselves along the way. It's not easy, but it's not complicated either, one foot in front of the other, one day at a time.
You mention you're convinced she has the disorder, and while a diagnosis doesn't really matter, it's the behaviors and how they affected us that matter, a lot of us have gotten value from this article at this stage:
https://bpdfamily.com/content/surviving-break-when-your-partner-has-borderline-personalityCheck that out, read a lot of posts, and post as much as you need to, it will get better. Take care of you!