I've been using the DEARMAN, SET, validation, and "disengaging from circular arguments" tools on this board, and they're really starting to make a difference, not only in my exBPDgf's behavior, but just the way I personally think about particular situations.
Today, we hit a breakthrough. I had my first visit with a new T, and my ex texted me afterwards while she was still at work saying "can't wait to hear about it!"...and I said, "Well I can't wait to tell you about it

". She called from her office about 10 mins later.
I barely got to tell her how the session went. She wanted to know about my plans for Friday night, because she was planning a surprise bday party for one of our mutual friends. I said that I should be able to make it. She then started talking about how it was difficult for her to send out all the facebook messages to everyone and invite them to come...but since I was the only one that had blocked her on FB, she had to call me. I said, "So, you're back on facebook? I thought you said that you were 'never getting on facebook again'?" (A few weeks ago, she had befriended my close friends on fb. I told her I didn't appreciate her doing that after she told me not to talk to her the week before. So, to "prove" to me that she wasn't trying to get my attention...she got off fb the next week and told me she would "never get back on it again" - obviously, I knew that wasn't true).
She immediately got upset. She starts saying, "What does it matter? You blocked me anyways! And I had to send out the invitations somehow and FB was the best way!" I said, "Well, couldn't (our other mutual friend) have done it?" Oh boy, that wasn't the correct thing to say. She starts flipping out and I stopped her. I said, "I was just confused because you said "x" would never happen, and then "x" happened a couple of weeks after you said "x" would never happen. I was only trying to get the facts straight." She starts going off, "its none of your business...we're not together anyways!" I said, "Please stop yelling or I will have to get off the phone with you." But she didn't quit..so I told her I had to go (in a very calm voice).
But after about 10 or 15 mins, after having us both have some cool time...I texted her, "I want you to know that I'm not upset about you getting back on FB. I was merely confused bc of how clear you made it seem to me that you were not getting back on it...so I started asking questions. I understand that you felt that I was being inquisitive, but I was just trying to understand the situation bc it confused me. I apologize if I upset you in any way as I seemed to have done. I think it would be very nice to see you tonight. I barely got to share any of my visit with you, and I would love to see you and tell you more about what we discussed."
She called about 5 mins later, mildly upset. It eventually turned into a circular argument with her going back to "well they're not your REAL friends if they accepted my friend request." I said, "you're certainly entitled to that opinion, but I do not share that opinion with you. If that were true, I wouldn't have ANY "real" friends. I can see where you're coming from on it though, but I don't share that perspective with you, and it's just best to agree to disagree."
She had NO where to go. She tried to say..."But that's how I feel!" I said, "Good...you're certainly entitled to the way you feel as well as your opinions. We won't agree on everything just like we won't share the exact same emotion at the same time. In any event, I still would love to see you tonight and I hope you're willing to meet up later." She said in a very nice voice, "I see. Well I'd love to see you too and hear about your visit. You're welcome to stop by after I get done at my grandma's..."
I'm amazed. I've been able to pull myself out of situations that could've gone bad. But I've never responded in such a manner that alows her to turn the bus around. Hopefully, more of these situations will be resolved like this!