Hi gmaforever,
Welcome to the BPD Family
I'm sorry you and your family are going through all of this. How old are your granddaughters? How do they seem to be handling things? Are they receiving any therapy at all?
I'm on these boards because my significant other (SO) has an undiagnosed BPD ex-wife (uBPDxw) so come at this from a slightly different angle.
That said the first thing I did when I found out about BPD was hit my library and read all I could on BPD. Two books about BPD in General that I found really helpful were... .
Stop Walking on Eggshells: Taking Your Life Back When Someone You Care About Has Borderline Personality Disorderby Paul T. Mason, Randi Kreger
Overcoming Borderline Personality Disorder: A Family Guide for Healing and Changeby Valerie Porr M. A.
I also wanted to point out the box to the right ---> each item is a link to more information you might want to check out the "Lessons" section.
My son said I would one day become the enemy.
Your son maybe right here, people with BPD do a lot of black and white thinking your son divorcing her could make him the enemy and you as well by extension. I've listed a few links below on Validation & SET (Sympathy Empathy Truth) both are tools that can help when dealing with your DIL. Validation is not about validating bad behaviors on her part but validating the feelings she is having behind those behaviors and SET is a way of communicating that also taps into her feelings. For people with BPD (pwBPD) feelings can often equal facts so focusing on her feelings can be helpful in your interactions with her.
(Validation can also be a good tool to use with your granddaughters)
https://bpdfamily.com/content/communication-skills-dont-be-invalidatinghttps://bpdfamily.com/content/communication-skills-dont-be-invalidatinghttps://bpdfamily.com/content/communication-skills-dont-be-invalidatinghttps://bpdfamily.com/message_board/index.php?topic=143695.0I know I'm throwing a lot of information at you, I hope you find it helpful. I know other members will be along soon with more ideas and feedback.
One more thing I wanted to suggest and that is see if your son would be willing to join us too. My SO and I are both members and we have found it helpful to speak the same language when dealing with his ex. Your son could get support in terms of exiting his marriage and support through the divorce process if he needs it.
Hang in there,
Panda39