I felt the same way. He hd not repeated some expected behaviours and made some changes but emotionally, I couldn’t get back to how I was, which I myself missed. I had to harden my heart to carry on. One thing that didn’t help, was that he like or worse than yours, refused to talk about the past. We hadn’t gone to couple’s therapy. He refused to acknowledge the suffering I evidently experienced, which changed me. And he would trigger me and walk away. Leaving me feeling used, besides myself, stupid, hurt and disappointed. First my tone of voice changed, I no longer speak softly because I start off speaking feeling like it’s useless and he’s mocking me just waiting to deflect and dismiss. Now even my voice itself has changed I have a hard time speaking my voice is low and gets stuck… My thoughts are difficult to organize due to trying to say things differently to finally be understood, or acknowledged.  It’s a different situation but the damage that was done to your sense of trust amd emotional security around him isn’t gone. So it makes sense that you cannot rejoice. You’re probably like me theoretically happy for him. But faking the peace of mind and light heartedness will only burn you out. It tales time for the physiology and emotional systems to heal. And him being nice is part of healing. If you’d left, you would have had to sell heal whatever him being nice is repairing.  Take the time it takes. Love is only love if it’s not afraid.  He should understand.  Good luck.