I'm sorry about Khan - hope it is just a UTI.
I think there is a way to celebrate a holiday without turning it into a Christian thing. Maybe you could decorate a tree outside with a few ornaments and birdseed ornaments and do some birdwatching for a couple of weeks. Instead of opening presents on the day, open one present a day like Hanukkah and then on Christmas Day itself, volunteer with meals on wheels or some other organization. Make a special meal and have it together with friends and make the day about being with loved ones and friends. Celebrate Kwanzaa, Hanukkah and Christmas and make it about learning about other cultures of the world. Write letters to loved ones with pictures by Dae enclosed. There are so many things to do to create your own holiday that it makes me a little annoyed with him that he can't seem to find his way around it. What a strange thing that he came home with a tree when he was so bothered by it all.
"Any idiot can face a crisis; it is this day-to-day living that wears you out." -Anton Chekhov