Hi Dan1966,
Welcome aboard. I am sorry that you are going through such a difficult time. The behaviors of people with BPD (pwBPD) can be really frustrating and take a lot out of their partners.
It is good that you are detaching yourself a bit, so you can focus on healing, centering yourself, and your needs. Throughout our relationships with a pwBPD, there is a tendency to forget about our needs and solely focus on our partner. Although we care about our pwBPD, it is important for us to be healthy.
It is great that you are establishing boundaries. Setting boundaries are really good for reiterating your need for space. Here is an article to help you get started.
BOUNDARIES: Upholding our values and independenceThere are various tools for communication on this site that are designed to lessen triggering and conflict. Communication tools have made a huge difference in communicating with my bf. Here is an article on communication tools.
TOOLS: S.E.T. - Support, Empathy and TruthIn addition to therapy, it really helps having a support team of family and friends. Do you have a support team? Also, sharing your story on here really helps. Perhaps you can share more of your story so we can help you better?