P2014,
My Ex telegraphed to me that she wanted to be something like BFFs while she was still living with me and conducting her juvenile r/s outside of our home. She didn't say she loved me, but, "I'll always have a love for you." I had bought tickets for a diva concert a year before, but the concert was postponed. She still wanted us to go on the "date" as "the kids' parents." I refused. How could I have enjoyed it? I would have been meeting her emotional needs.
What helped me a lot in detaching, as tough as it was, was to practice the Joe Carver form of detachment, because in a sense, that's what it was. Bland, boring, as emotionless as possible. We weren't married, so had no assets to divide (basically, it would have been dividing my assets since she brought nothing into the r/s), but we had child custody issues to negotiate.
Article 10: Leaving a Partner with Borderline Personality DisorderAs painful and traumatic as it is to see him move on like that, I would take advantage of the idealization phase of his new r/s. pwBPD seem to be consciously manipulating, but for the most part it's just their unhealthy coping mechanism. You can take advantage of his behavior and turn it towards your favor until your legal matters are settled. Deal with your emotional pain here, and with whatever support you have in real life.
Detachment comes in stages, each stage a little less painful than the last. Dealing with legal issues necessarily keeps us attached for a time, but that too shall pass. Play the long game.