Has anyone ever had a calm breakup with a pwbdp?

Last night I told him that I want to break up. I was prepared for the worst possible reactions, and it actually ended up being very mild. He started to slip right into blaming, but caught himself and stopped. He said he wasn’t saying too much, because he knows how hard it must have been for me to say that out loud and doesn’t want to let his emotions get the best of him and make things harder on me. He then asked if he could stay until he finds a place, which I’m okay with as long as things remain peaceful.

I can’t tell if I’m being manipulated. I have been sharing a lot over the past few years with him about emotional regulation and other healing skills that I am learning to help with my CPTSD, and he has learned some of it along the way, but my mind is completely blown at his lack of reaction, so I’m not sure if I am wrong about him likely having bpd or if he is actually healing and managing it better or if this is complete manipulation. I have such an uneasy feeling, like I’m just waiting for the other shoe to drop now. Anyone experience anything similar?