Selfishness and Entitlement are just part of this MLC thing. Sorry to tell you its just a part of the whole package and for me are indicators that the crisis is alive and well.
I can not tell you what will happen for you and your sitch as they are all different but I will say for mine the holidays always sparked movement as my W/STBW/Running out of things to call her ... is/was very family based and Thanksgiving/Christmas are the high conflict days. I pretty much give up Christmas as she likes to take S up to her parents and he can celebrate with the big family .. cousins and the sort ... Thanksgiving we split. For me the day does not matter as S and I celebrate our own way on our own time with new traditions and all.
Its hard at first, but know even though she may not show it its hard for her to ... be the rock and pick your battles but above all things put those little ones first ... they are whats most important during this time and will thank you for not making bad memories over what should be looked back on as good times.