
Prayingleo,
as JRT pointed out - getting him to get into therapy would be a big step forward, particularly as you are at the point where he acknowledges that there is a problem. It is excellent that you have already taken steps to reach out and have a T. Therapists are good in reminding ourselves of the duty to ourselves and children.
but mostly now I spend my time trying desperately to do everything right so he doesn't rage
Yeah, that boils down to the infamous walking on eggshells. Here is BPD rage avoiding 101:
1) Do not avoid triggering him - loosing game. Do avoid invalidating him. Invalidating is the most common and predicable trigger. It is also eroding his ability to self validate. It is very common in a distressed relationship to invalidate our partners. One of the easiest and quite common way to invalidate is e.g. to tell our partners we love them when at that very moment we are raging mad at them. If we do that we are deluding ourselves that our partner won't sense our anger. We lie about our emotion and invalidate them. Learning how to address negative emotions is something we can learn that has a big impact on navigating the emotional labyrinth of our partners and sooth them when possible (not always but often). Avoiding invalidation is a negative focus and a hard thing to do - focus on learning validating him leads naturally to decreasing invalidation on both sides.
2) Rage that is isolated to the relationship is often related to combination of a pwBPD and weak boundaries. Crumbling pointed you for good reasons in that direction. Once a few boundaries have been established rage is greatly reduced. The board and your T can help you figuring out where to draw the line, how to draw it and stand behind you when you draw it.
Again welcome to the board,
a0