In your first post I zoned in on you being done.I think that is best for you now. Just decide what that will look like. Don't let it be an angry bitter place. I don't think you are ready to have a healthy R with anyone else just yet, but yes you deserve better treatment. That day will come.
Don't worry about the reasons W is wanting to go. Maybe she has no other options. Regardless of the reason, I doubt it is to punish you. It is inconsiderate all the same. I can understand that it being far away she wants to make the most of it. Again selfish.
Did ye ever formalise a schedule for kids. If not that is a priority now. Maybe even if ye have to sit down with a lawyer or other authority figure to negotiate THIS Christmas. The vets can say if that is too hard a reaction but you have your rights too.
If you do not manage to negotiate a partition equitable this year, be clear that next year it will be the opposite I.e. 100% with you.
I am sorry you have bad associations and memories of new years.I do agree with the others that maybe you could start anew and create other memories,traditions etc .
I understand your hurt and anger. Hopefully they can serve you to drive your construction of a better life without W. 2017 will be your year and you will make it better.
Best wishes
R 25 years M 14 years S11 & S13 Working on it alone since Oct 2014 M in trouble a lot earlier (~2 years) Feb 2016. 1st R chat in a yr. Next R chat Aug'17 Still together