Some more thoughts on ways to de-commercialise Christmas:
A friend of mine spends her Christmas Day serving meals at a shelter for the homeless. Various local churches have a general gathering for people who would otherwise be alone, they often welcome an extra pair of hands. It exposes you to people who otherwise live lonely, impoverished lives.
Other people I know will spend their day at nursing homes (especially the low-budget ones) taking small gifts (a bar of soap; a new face washer; a lavender bag) to hand out. Don't take food items unless you check with the staff first, in case the person you are giving it to is not permitted that food on their diet (they could be diabetic, they might be restricted to foods of a certain texture).
There are ways to teach children the good, giving meaning of Christmas in a positive way.
When I was a child I was also hooked on the gifts and "what will I get?" side of Christmas. It's only natural. But our church also used to take the young people carol-singing at night on Christmas Eve, travelling around the community to sing carols outside the homes of people who were ill, elderly, isolated in some way or just chosen at random. I learnt to see the happiness we brought to people and enjoy it. It was a classic Pavlovian conditioned response - while we were doing this good deed, my mind was still caught up with the anticipation of the next day's gift-giving, but over the few years of my youth I came to enjoy the carol-singing for its own sake, and to really look forward to it and not the gifts (which were usually an anti-climax anyway). By the time I was ten years old, when I looked back on the joy of each previous Christmas it was to remember the camaraderie of singing together to make other people happy.
That didn't happen overnight. It took several years of getting that lesson.
Laws have changed, society has changed and we can't sing carols on Christmas Eve like we used to; it's just not the same.
Children are born to be selfish. A newborn baby is programmed to let you know by crying, when he needs to be fed or is uncomfortable. Everything the baby does revolves around getting what he wants. As the children grow we try to change them from this into creatures more aware of the need to belong to a larger group and consider the needs of the group rather than their own. But it takes time and often only happens partly. Most adult humans are also basically motivated by self-interest. We work, as a society, by 'selling' the idea of teamwork, but mostly we use the carrot on the stick of "what will you get out of this, personally, for helping me?"
As for breaking presents so soon after Christmas - I remember a nephew of mine whose parents were wealthy (at the time) but time-poor. They bought some lovely gifts for their son for Christmas, I remember I had a lot of fun playing with him with his toys. But I also saw him making concerted efforts to break them, as if testing to see how tough the toys really were (he was a good ad for Fisher-Price, I recall). I felt so sad looking at him - he had always had anything he wanted in terms of toys. But as a son he was sidelined. I'm glad he's grown up into a son who is close to his parents (now poor - they went bankrupt when the boy was in his teens).
We sometimes teach our kids to be selfish, even when trying not to. It's so hard. They cry that some kid at school has such-and-such a toy and he will die if he doesn't have it. We walk a parental tightrope between over-indulgence and envy. And often the kid has both to contend with - getting too much and STILL not happy.
difficult child 3 has been especially difficult to teach "don't be selfish". What has been working best on him, is getting him to manage a budget, to be spent ONLY on other people. He has to shop around, look for a gift suited to that person but not spend so much on one person that he hasn't got anything left to spend on anybody else. He then has to wrap the gift (removing the price tag, of course) and write a gift tag. He then has to wait (keeping the secret) until it's time to give the gift. We talk about the gifts, what we will give the person and why. Of course he gets excited (and impatient) about his own gifts (what he's getting) but he is slowly getting the 'giving' message. We've tried many things, this is what has worked best for us.
The trouble is, it takes time and energy, things which you sound very short of right now. I agree with those who have suggested respite - even if you only have one at a time in respite, it would help (divide and conquer). You could work with each child individually, maybe have more chance of getting through to him as well as getting your own sense of perspective and control back.
I wish you the best with it, and if I don't get to communicate with you before, I hope you all have a better Christmas and New Year than you have anticipated. I wish that for all of us.
Marg