Holidays - Together Or Apart?

Last year, my then-boyfriend, now fiance, and I spent the whole of the Christmas holiday with his extended family (who I was meeting for the first time). This took place thousands of miles from my own family and where my fiance and I currently live. Heretofore, I had never missed a major holiday with my family.
This year, we are scheduled to spend the holidays with my family. This will also be his first time spending Christmas without any family members.

Before I had gone to spend the holidays with his family, we had come to an agreement: we will alternate years with his family and mine. There is understanding that stuff happens and there's a need to be flexible, but that's the plan.

Now he is saying that, although he has no intent to back out of this year's plans, that he would like to spend some holidays apart in the future.

To me, this is unacceptable. The only time when I would like to spend holidays apart is if his aunt is dying and my sister is giving birth - or some such coincidence of important, singular (or nearly so) events on both sides.
This sense that being apart for the holidays is "fine" subverts what is, for me, the very meaning of holidays. I envision holidays to be about togetherness, family, love, and all of that.
Being separated from my partner because he "feels like it this year" thus does not sit well with me. With our upcoming marriage, we become our *own* family. In my estimation, then, our personal brand-new two-person family then becomes the central family for each of us - both of us.

I very much understand and have come to accept that I cannot be with my family during all the holidays because of our relationship. I was sad to miss Christmas with my family last year, but I enjoyed the holiday with my new family.

I think he should embrace the original every-other-year compromise and stick with that as our general plan. [Knowing that it can be amended as needed in light of familial circumstances, rather than a whim.]

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