I am so lucky really. My kids are all vaccinated with boosters as am I and my partner. But - we still don't want to take any risks at all. They feel the same way so there is no problem or pressure. We'll exchange a few gifts on the doorstep, maintaining distance. You are right to take a stand on this I think, however difficult.
I think you are being more cautious than you need to be. Dr Fauci (our leading authority figure here) and the CDC have both said that it is safe for fully vaccinated (especially if boosted) families to get together for Christmas. My parents are 87 and 89, and we are all triple vaxxed, and we are getting together for Christmas Day.
CD