Hello amusement park, and welcome to bpdfamily.
The push/pull, mood swings, impulsive spending, blame shifting, explosive anger are all possible indicators of a personality disorder. It is very challenging to maintain a positive relationship with a spouse, family member or friend who has BPD, and it is pretty standard to react in ways that actually make the situation worse. You are not alone in that.
Actually, disengaging is important when your wife becomes abusive or emotionally dysregulated, but there is an effective way to do so that won't make things worse. There are some excellent communication tools here:
https://bpdfamily.com/message_board/index.php?topic=56206.msg913188#msg913188https://bpdfamily.com/message_board/index.php?topic=56206.msg913190#msg913190The basic understanding is that we have to stop making things worse in order for them to get better. As you read some of these tools, you may see some of the things that you have done that don't work, and maybe somethings that you could try to disarm some of the high emotions. In the end, the choice of staying or leaving is a very personal one. The members on the boards can help you with the been there/done that support that is really valuable as you work on your own path.
I encourage you to keep posting and asking questions.