Thanks, an0ught, that is very helpful. I think the structure element is going to be key-- I have set fixed days when I'm going to be out working, but she's managed to stall me by acting out as I'm getting up on those days. I do think that would work better if there were a clearer structure to it, and I bet she'd even be willing to make some suggestions about what structure might help her. She knows that this is a problem, and can make plans for it when she's got some distance. But, in the moment, she always just seems to get so worked up that anything she's thought about before doesn't matter.
I need to work on my validation skills-- its not one of my stronger areas. I'll admit to having some not-very-pretty thoughts when she admitted she felt abandoned when I went to work. She has a very full life, with friends she sees a couple times a week, activities she does with the kids, time to read and write and spend outside. I've pretty much got work and family (which I'm working to change). So hearing that she feels like she needs even more of me than she's already getting is pretty hard.
Boundaries also a work in progress!
Any thoughts about the kids part? I just can't get around not wanting to leave her that mad when she's got the kids with her. That's a hook she can always use to pull me back in. . .
leaving situations are hard for pwBPD so there is no solution but only mitigation.
1 Structure. You wrote you got some freedom and little structure. This is not good as it puts maximum responsibility and guilt for abandonment on you. You may at the moment try to minimize leaving and feel guilty for it - this guilt will be sensed by her and proves that you are really a bad guy! It would be better to have a more fixed structure in place with fixed day and fixed time when you leave. It may not be as optimal for the work or it may require you to stay away a little longer once in a while but becoming more predictable allows better planning and adjustment for all.
2 Validation. Address her abandonment, the unfairness and the terrible loneliness she is facing. She is angry as she can't vocalize what she if feeling so targeted validation can be of help here.
3 Boundaries. When leaving don't let her get away with game playing. Read up on boundaries and do proper planning. Having more structure will help knowing where to draw the line but actually executing it needs preparation and commitment. She is used to game playing so an important toy is taken away and she is going to be upset.