This did sounds very insecure and she seems to want to cut off everything and everyone who was in your son’s previous life. In a minor way we have this with a sil who will never attend family gatherings and never visit us though we are allowed and I mean allowed to visit them , only if we ask, of course. It is so sad and I feel for you missing a dear gc. Would it help if you sent a card or something saying how much you miss them all and maybe you could get together, if only in a park or somewhere neutral? If you are always nice and friendly and don’t give her any reason whatsoever to turn her back maybe she will mature a bit and stop seeing you all as a threat? Not easy because she sounds like a nasty one but do your best. Can you ring your son privately and say how you feel? He may not realise.
what is this behavior called does it have a name?
By special request, let’s discuss our favourite Classic Music and why?


