One of the best things I heard years ago about feeling blue and irritable on Christmas came in a Quaker meeting. Someone stood up and very simply said something along the lines of "As angels, animals, shepherds and wisemen all gathered around the infant Jesus, we should not be afraid to bring all of our feelings, good and bad, into the Christmas season." Trying to be happy or excited all the time, and the time is extended every year, is exhausting and can burn you out. I need quiet time and alone time or my family time disintegrates rapidly and badly.