Some various photos of Hitler on Christmas over the years (the top photo is from 1926). He did not enjoy Christmas and wanted to be alone on December 25. He told people it was because his mother had died by the light of the Christmas tree. 

When Eva Braun’s mother asked her why she was never with Hitler on Christmas, Eva said, “leave be, Mutti. He had such a horrible Christmas as a young man that he wants to be alone on that day.”