He must have been floored by her response to his comment that he was my boyfriend as, according to her, it was pretty withering and she questioned whether I would have described him as such. He may well have regretted saying it.
umm, could this possibly be why he might have eased up in the past few days? Could it be he wonders what you have said to your daughter about your relationship such that your daughter would say "I'm not sure mum would describe you as a boyfriend"
whew, you know it does sound like miscommunication all around.