It might be good for you and your family if you re-examine your thoughts and feelings about the Christmas season. I was raised as a Catholic but stopped believing in the "fairytale" as you call it when I was still just a boy. In spite of that, I had wonderful experiences with family and friends at Christmas and carried that through to adulthood.
I realized as an adult that for me personally, Christmas is about togetherness with family and friends, and a kind of "wrapping up" of the year that's about to end with gratitude and some celebration. If you looked at it in this way instead of as an irrelevant religious celebration, you might learn to enjoy it. The way things are now, your attitude toward the season is probably putting a serious damper on the enjoyment of the rest of your family as well as yourself.

