Hi lost6891,

What would you like to see happen? What are your gut feelings about your marriage?
I agree with Lucky Jim only you know if you're truly done with your marriage or not, I understand that it's a complex decision, regardless of what others outside of your marriage looking in say, you and you're wife are the ones in the r/s. You can't force her to take therapy, it's her choice to go or not to go, she can blameshift but that still doesn't change the fact that she needs help.
A pwBPD will usually get help when they've hit their rock bottom and rock bottom is different for everyone. Who knows maybe this event is the catalyst for change? Her parents don't seem interested in helping her if they're contacting you. You've explained to them what your intentions are and I'm going to suspect that you were clear that you were not going back.
You might want to go NC with the family too for now, I'm sure that others can relate with your situation if a pwBPD are left they don't accept the fact that the r/s is over and will keep trying, I feel bad for those members. If the pwBPD has left you usually you're split black and you don't hear from them as painful as it feels it has to be harder when you're trying to heal and your expwBPD won't accept that it's over.
Your wife has a serious mental illness, in that context her behaviour makes sense a pwBPD fear being alone, she's an adult and she has a responsibility to help herself a pwBPD have dependency issues and are dependent on others for things that they should really take care of themselves. You were her fixer and helper at one time, it enables her dependency. If you go back how are things going to change? Are you willing to be the one that's going to have to change for your marriage?
We can't tell you what to do we can listen and give you feedback and as Lucky Jim said listen to your needs, there's judgement here if you go back but you have a right to be happy in this life.