Hi, Maltacar, and I'd like to join
pessim-optimist in welcoming you to this site. She had a great suggestion to you to check out the links to the right-hand side of this page; they will give you the tools and techniques you need, to learn how to understand and deal with your daughter.
I'm so sorry for the pain that the relationship you have with her is causing you; it's terrible that she sometimes uses your granddaughter to try to control you. As a grandmother myself, I know that a situation like that is so sad and hurtful. I am on this site, actually, because my adult son (36) was recently diagnosed with BPD, and the first things I read on this site were these links:
Communication using validation. What it is; how to do itTOOLS: S.E.T. - Support, Empathy and TruthI found that once I understood how his mind works, and learned the correct way to communicate with him so that I didn't push every button that he has, he began reacting differently with
me, and things started to get better immediately! You are so wise to come here and want to learn the tools and techniques so that you can deal with your daughter better... .And I can tell you for sure, it really will help. Please continue to tell us your story and ask your questions, and read everything you can; we are here for you