It is good to know you are safe now and I think you did a good job telling her you would leave if she ever did it again. Another option would be to call the police. Being attacked with a knife as you describe is pretty serious.
My biggest challenge is when she’s been triggered, I’m usually the object of significant criticism no matter who or what actually triggered her. She says I never listen to her concerns. I say that I would love to listen to whatever she would like to say as long as it does not involve unwarranted criticism of me. She feels that is too restrictive. Her ever ready list of my faults leaves me feeling depressed and worthless. I’m looking to receive counseling tomorrow. She refuses to accept any kind of help for her or us.
I can see where this is very troubling behavior. Saying you will not listen to verbal abuse is good. The thing is, it is not likely to go over well as you have seen, at least not in terms of her accepting it. The great thing about boundaries though is that the other person does not need to agree with them. We do. That means we state our boundary (I understand you are upset and I want to help. I also can not listen to you calling me names and putting me down) and then we take an action (end the conversation, say you are going for a walk and will be back in 20 minutes, go to another room etc.).
We do not need to sit while we are being verbally taken down. We can set limits. We can also,
before they become dysregualted, try to use communication tools that can help defuse the situation. Validation can work sometimes. Once a pwBPD (person with BPD) becomes dysregulated there is little point in trying to validate though.
At that point, implementing boundaries is really the best option along with keeping in mind not to JADE (see
Don't JADE).
At this point I am not sure what else to recommend but we can figure things out as you post and share more details. I would like to hear your thoughts about the article I posting on not JADEing. It was a big eye opener for me when I first read it. When we justify, argue/attack, defend and explain we set our self up for a no win circular argument and at the same time, we end up invalidating our loved one even though we do not intend to. invalidation can be a huge trigger.
So when you can, share your thoughts. If nothing I wrote applies, let me know and we can chat some more.