I'm not really sure why you would want to spend Christmas with your family. They don't sound like a very pleasant bunch.
There sound extremely entitled and selfish, they have no empathy for the amount of work and time and money that you put into providing them with a wonderful meal and visit. They contribute nothing. They don't feel bad about it, and the more you do for them the more they expect.
They are trying to guilt you into continuing being their free meal ticket and slave so that you can pay for everything, do all the prep, do all the work, do all the clean up, pay the bills, and they get to sit back play on their phones and have a good day.
You've been doing this not one year, not two years, not rotating years, but you've done it for 7 years. I think that's at least 6 years too many given how they're acting.
You've got 24 days before Christmas, more than enough time to tell them no I'm sorry, can't host it this year...
I don't know what your home/work/partner/children situation is, I haven't been able to read all the posts yet, but if you want to take the easy way out, just come up with an excuse that has something to do with your home/work/partner/children which they may see as being not much more than an excuse but, oh well...
(If you really can't stomach the idea of coming up with a "fake excuse", here's an alternate suggestion to make your escape from the terrible family Christmas a genuine one...
See if there's any place locally that you can volunteer your time on the day that you normally would be hosting the Christmas party. Like for instance, an animal shelter, perhaps you can walk the dogs or brush the cats, they still need to be fed and played with and the litter boxs cleaned, just because it's Christmas, they don't know the difference. They are in need.
Or if you like the idea of volunteering at a local church who might be doing a community meal, or something like that. Find a way to give your time and energy to those who actually really will appreciate it. Not your family because they obviously don't.)
Or if you feel particularly brave/angry enough/empowered then be 100% honest with them and tell them the truth, but it will not be taken well.
Be prepared that no matter what you say, because they're not going to be getting their own way, they are going to be mad. They have zero right to be, but they are selfish and shortsighted and entitled and takers who feel no empathy with you and feel no guilt at what they've done and don't understand how unfair they've been, because they don't care. So, they will find a way to blame you for ruining Christmas. Be prepared for that. If you're following them on social media, be prepared for some really nasty posts about how you ruined everything, be prepared for them to badmouth you to anyone else that they know about how horrible you are and how you've ruined everything, I mean, 100% unfair and untrue? Yes it is but they sound like the kind of people who would do this so you just have to be prepared for it...
I wish you a stress-free (and actually happy for a change) Christmas.