I'm a staunch atheist who likes a holiday.
Jesus was most likely born in the spring or fall a few years earlier than we recognize, if he was even a single person or existed at all. The Church, as it did every time, took existing holidays and co-opted them.
The end of the Roman calendar year is an amalgam of pagan holidays that celebrate the shortest day/longest night. A lot of the traditions we associate with Xmas are celebrating the beginning of the lengthening of the day and the return to life/springtime.
Xmas has always been a meta holiday. Most are. Enjoy the company of friends and family just as people have for millenia, no matter what banner is hanging over the mantle.