Long post but I need an AIBU here....
Back story;
Partner and I have been together a couple of years. I have 2 DCs full time from previous relationship and we have his 2 DCs half the week. All 4 are same ages between 7-9. Last Xmas (I had just had new baby) we invited both exes to share Xmas morning with us - 'they' have always had alternative xmasses BUT gone to each other's in the morning to watch them open presents. So thought this would be a nice, everyone together, first Xmas all together, easy transition for the kids seen as though there had been so many changes within the one year. Bear in mind, myself and SC mum do not get along. But that's another story that includes her refusing to acknowledge me as their SM and constantly finding one issue or another and general attempted micromanaging and bullying. ANYWAY, I made the effort, painted on a smile and it went fine.
Fast forward to this year, I am pregnant with my 4th, 2nd with partner - taking total number of kids from 5-6 after the new year. It's her year to have SC and partner is wanting to go up and watch them open presents, but doesn't want to miss out here so trying to navigate this. I don't particularly want him to go as he would be collecting them late afternoon anyway and we can do our presents then.
He doesn't have to be there to play happy families with them, just because that's what they've always done. But apparently this is what's happening.
I have also said that next year, I don't want her to come to us. It will be our 2nds first Xmas, our DD will be 2 and more understanding of the whole day and I just don't want to share that with her. Especially as only 2 kids out of 6 are hers and we don't get along. But he thinks I'm being unreasonable and the argument that other families take a day or a half a day each (like my parents did when I was little (Xmas with mum, boxing day with dad)) is not the norm.
AIBU and should I just suck it up and deal with it? Or stand my ground and hope he understands that things are allowed to change now we have our own growing family and he can't expect things to always stay the same?