Welcome Stormy76:I'm sorry about the problems with your mom. It doesn't matter if she accepts the label of BPD. You can't change her. All you can do is manage your boundaries and the way you interact with and react to her.
Your boundary about your children sounds wise. You definitely want to protect them. Your mom's behavior is her own choice and she will be the one responsible for restrictions in regard to your children.
It will be helpful for you to read about FOG (fear, obligation and guilt) and BOUNDARIES. You shouldn't feel guilty about asserting a boundary with your mom.
There are links to is a lot of helpful information to the upper right of this post. The additional links below could, also, be helpful (click on the green words, or the green address):
FOG BOUNDARIESThe additional links below, contain info. about validation. Validation doesn't mean that you agree with someone's position. You don't validate what is invalid, but you acknowledge someone's feelings. More importantly, you don't want to invalidate.
VALIDATION VALIDATION - DON'T INVALIDATEAVOID CIRCULAR ARGUMENTS Check out some of the lessons (at the links above) and let us know what you think. It can take some practice to gain benefit from some of the skills. Many people gain benefit from sharing and gaining input as they try new skills. I look forward to hearing more from you.