Hi Gunnered,
Like Loosestife and Determined have said welcome.
I vividly remember the confusion and desperation I was feeling the first day I arrived here. Gentle calm people pointed me first to the lessons on the right side of the page and I felt like I was reading my own story over and over again.
There is a lot to absorb here. BPD is a very complex disorder and our reactions to it add even more complexity. It's going to take some time to gain some understanding of the behaviors going on and how to best respond. BPD thinking is predictable from within they way the disorder processes information. There are tools for communication.
Just like Loosestrife I noticed you said you wife hits you. That's never acceptable. Stopping the cycle of conflict before it reaches the stage of throwing things and hitting is very important. I understand you don't feel in any real physical danger. However the level of conflict you are describing isn't good for either of you.
In the simplest sense when the rage starts to build walk away, say something like 'I can't participate in this conversation right now' (put it in your own words) but remove yourself from the argument. Walk the dog, go to the store, take the trash out.
I know more senior members will be along to welcome you. I am glad you are here. This is a good place. I've learned a lot and it's helped me more than I can say.
try this link
https://bpdfamily.com/content/ending-conflict'ducks