I agree that organization and routines help so much. They seem to provide a sense of security even during an unpredictable storm.
Meditation is my rock: becoming deeply rooted, in touch with my inner self, helps me see the bigger picture and the beauty of even the most trying situations. After all, even "mistakes" can serve us as learning experiences -- from simply realizing what we don't like (and therefore, getting closer to knowing what we love) to becoming stronger as individuals, and learning to put faith in ourselves and the universe (whatever your world view) that things will all be okay in the end.
Also, I find a great deal of peace when I reflect on my "wants" versus "needs." While I want all of the trimmings of the holiday and for everything to be well in my world, all I actually need in life is my life, the breath in my lungs, my soul. And as long as I have my mental faculties, my imagination is capable of wonders! And if I don't have my mental faculties, well, I won't know any better, will I? LOL So no matter what, everything will be okay.
When all else fails, I take a few deep breaths, paying attention to them, which returns me in consciousness to the present moment. With my thoughts settled into quiet peace, I then take stock of the situation at face-value instead of resisting and looking away (my surroundings/body/etc). From that point, if I can take action, I do, but if I can't, acceptance is all there is. To fight the situation only feeds unhappiness and wastes energy that is especially precious during trying times, when energy seems to be at its lowest ebb. When I have accepted, a peace settles within. At that point, I have done all I can, and again, I reflect on the fact that everything is going to be okay. "This too shall pass."