Pghinnyc,
I totally hear you. From what you wrote I can imagine how it is, since I'm also familiar with some of those situations.
I'm sorry you have to go through this. Of course you love her, otherwise why would you still be there? You may also feel compelled to try to help her, because you realize that deep down she's really unhappy, too. But sometimes to help another person you have to help yourself first.
Coming here is a big step; there's a lot of useful information for coping, and reading posts from others can help identify patterns.
I agree with JongoBong that breaking out of your isolation may be helpful. I was in denial about my own situation for years, forbidden by my wife to talk to close friends or family about problems, strongly discouraged from seeking therapy for myself until finally it got really bad for me and there was no alternative.
As Jongo said,
"I bought into this for quite a while, until it began to be an issue with my personal safety. Don't let this happen to you. "
I second that. The point is, once I did start breaking out of isolation, I shared my situation with a therapist and a very few close friends, I began to see things more clearly. The fog lifted a bit, just enough to let me read books on BPD, keep a journal, spend time on here, get therapy, reach out and make more friends, and it all began a healthy cycle. It's not great for me now, but its worlds better than it was.
The best part (haha, maybe I say this because I still have co-dependent traits) is that my uBPDwife is happier now too. All of this change I did, eventually stimulated change in my wife, also. She is in DBT now, thinking about changing her job, she reached out to her family, and our relationship is much smoother now. We'll probably still separate, but I can tell, she is much happier and better able to deal with life than she was. That's a great reward.
"If you're going through hell, keep going." -W. Churchill