Not celebrating Christmas? I wish you the merriest of quiet Christmases, entirely free from the looming spectre of Santa Claus, an out-of-season Baby Jesus, and the incessant jangling holiday music. Peace be with you. (In fact, if you are celebrating Christmas, may the angst of the season give you a miss as well.)
Not celebrating Kwanzaa? I wish you a week of the finest unity, self-determination, community in a number of different flavors, purpose, creativity, and faith. May you never want for books and the heritage of your culture, whether it be the culture of your birth or a chosen or rediscovered culture.
Not celebrating Chanukah? I wish you the happiest of Chanukahs, one of miracles, peace and plenty, with all the light and sacred supplies you need, without an invading army knocking down your walls.
Not celebrating the winter Solstice? I wish you the happiest of Yules, and the continued rotation of the Earth and its progress along the orbital path around the Sun, and no disruption to the regular wobble. Let's hear it for the progression of the seasons!
If you celebrate all of these or more, enjoy! But if you don't celebrate, know that I wish you the happiness of the holiday spirit without the occasionally-obnoxious trimmings.