I'm a Husband to Undiagnosed BPD and Feeling Hopeless

I'm Bryan. My wife and I have been in and out of counseling for a few years, mostly with things being unheated enough to warrant a distress call. But earlier in the year we were in counseling as it just seemed all of it was just crumbling down. She has a history of very angry and critical behavior, and I have a history of trying to avoid conflict as much as possible so I "don't anger the beast." (She's not a beast, she's a good mother to our three daughters and ultimately a very likeable person.)

She does not often admit to being wrong about anything and often has a kind of God complex, which has made rocky relationships with her own parents, her brother and sister-in-law, most friends we've had, and especially ANYONE in my family, causing me to live most of my life living far away from them and with very little personal interaction with my parents and my brother. She has had a rough history with work and has been in and out of jobs since before we were married fifteen years ago, usually walking out on the spot if she is ever corrected on anything or has an issue with her manager or supervisor. She is a good mother in a very tough-love way, making them learn lessons is the most important. And when it comes to me or our kids, she will often get upset and then rant and rave on any of us and can literally do this for HOURS, even if everyone is in tears and upset. Back to our counseling sessions - I was brave enough to be honest with our counselor about how this behavior has affected me and others, and he mentioned that these sound like symptoms of BPD. He sent me a book to read and while she didn't fit severe cases (she has never attempted suicide or self harm to the best of my knowledge). He suggested she may have a high functioning case.

She was LIVID. She immediately forced us to drop him as a counselor and find a therapist who could focus more on the marriage and everything I have done wrong (I admitedly am not perfect, and while I've never had a sexual or physical affair, last year I got too close emotionally to someone else and came clean about it, which threw us back into counseling, I am not proud of this).

She has about two good weeks out of the month but then becomes so angry at almost anything. I am not sure what to do with all of this. I need support for one thing, but I also want to help her, but she will absolutely not face anything that points a finger at her. She won't even get tested for it, so I'm not even really sure WHAT I am dealing with. Sigh... Just need to vent.