Hi Mike_confused,
She has been in CR for a year and a half. For a long while everything was the greatest in the program. Now she has gone from white to black regarding the program, having many conflicts with individuals in CR. It seems to me he problems with these individuals stems from her perception that she is not getting the attention she deserves.
This is typical relationship development for a pwBPD: Falling in love and then painting black after getting real close (inviting her home).
My possibly simplistic way to un-confuse the situation: These are her relationships - she messes up - she bears the consequences.
Look at the alternatives - you step in - try to fix
a) something goes wrong - you get blamed
b) you find a fix but she needs to change - you get blamed
c) she considers your interference as betrayal - you get blamed
now you stay out:
d) she messes up - the only person she can reasonable blame is herself - you probably will get hit some fallout but your conscious is clean.
Before looking at constructive steps one can take let's understand that painting black serves a function - validating the negative emotions in herself. Taking away the black painted object will lead to increased pressure on her to find another target (maybe you) or dsyfunctional negative behavior (maybe cutting) to serve the function. The black painting is her projecting what is inside her head. Fixing the world is fixing the side that likely needs less fixing.
The problem is that my BPDw is not entirely wrong about this particular woman. I just do not know how much her surging emotions are magnifying any issues within CR.
Of course your wife is not wrong about her. There is always something wrong in people. And it would not be surprising to find out that a pwBPD seeks out another pwBPD or at least some issues. Projection is not about creating a new reality it is about distorting reality.
Challenging her view of reality is going to be tough. You are too close to effectively do it - a T would be in a better position there. Right now you are new to the board and not so familiar with the tools so maybe the best is to limit your involvement in the conflicts with third parties unless you are directly affected by them. Think about this limit as a boundary - don't give her relationship advice - her problems.
While you can limit the advice you certainly need to validate. You will need to validate her frustration, her seeing serious - possibly extremely serious problems with this other women etc... Her emotions after all - you may see a molehill while she sees a mountain - for her it is Everest! You may need to validate her frustration with you not giving any advice (but if you would give you will be blamed... . ) - possibly you are simply ignorant in handling women problems .
That will go a long way in enabling her to work through the problems - after all she is the only one who can do it. She may or may not break off the relationship with the woman or the CR although I doubt it a little at the moment - the intensity of her negative emotions indicate a strong relationship - just the wrong polarity.