Hi
Brokendaughter,

Welcome to our big online family! We understand the dynamics of what you are going through, and so many of us have been there or are there now. It's such a tricky walk, isn't it?
When a pwBPD is showing signs of symptoms of typical behaviors, a situation such as what you are experiencing is very black and white to them. My uBPDm felt that we were betraying her if we paid attention to any other family member besides her, especially one who had hurt her in some way. We became disloyal to her, and she would almost cut us out of her life.
Here is an article that might give you some insight:
Fear of Abandonment Does this seem like it might apply to your situation at all?

Wools