My BPDexbf seemed to enjoy, smiling inappropriately when I was clearly upset, or expressing my feelings. Especially, when he was clearly the source of that pain. Why
I only saw this at the very end of our marriage. My xBPDh clearly enjoyed telling me about the replacement. He slowly revealed little details without ever giving the full story. He was really getting a kick out of my pain and bewilderment.
I think it was some sort of warped revenge for all the wrongdoings I may or may not have done to him during the years we were together.
As for this behaviour whilst still in a relationship, I think it comes down to control. He may have enjoyed being able to 'make you' be upset.
Sorry you went through this. I know first hand how painful it is.
I as well saw for the first time, at the end of our marriage, how she seemed to enjoy seeing me in immense pain. She would tell me wall about her deep
feelings for the replacement. She would also withhold certain information about their "amazing connection" by telling me she was afraid that if she told
me everything I would just get more upset. Somethings are more painful when left to our imaginations. This added to my pain, not help relieve it, she knew this.
She would also go on and on about their special connection, knowing and seeing how it effected me. She would say, "at least I'm being honest with you".
There were times close to the end when I would be crying my eyes out after hearing about the OM. I would look up at her and she would be smiling!
Her response would either be "I didn't realize you loved me so much" or "i don't understand why this is upsetting you".
She hadn't an ounce of empathy.
I'm not sure it was pleasure she was getting from my pain though. I think she was milking my emotions in a way that built her self esteem / confidence. If she
could make me this upset by her moving on with another man she must be worth something. It was like a form of sick validation to her. She fed off of my pain
and grief. It wasn't about pleasure. It was about feeding off my pure, raw emotional energy.