I think my advice would be to wave them off happily for this year, they may well change their minds for next year if you do.
For the first time in 45 years my eldest son will not be spending Christmas with us, or even in this Country. He has chosen to take himself and two granddaughers abroad to live, so we can't see them, he won't allow us to go over there to visit, and says he is not going to set foot in thid Country in any foreseeable future. And yes, it hurts like hell! No falling out, he is happy to accept presents, (but says he is too poor to give them, or even a card) his wife lives with us three days a week for work, he just sees no need to see his parents at all. DiL did sent us photos of GD's eighth birthday, ( GD blowing out the candles on the cake I had made for her to take out), and I could have cried with longing.
Enjoy finding suitable presents they can take out with them, and wish them well. If you manage that, they may well be back with you next year, and alternate after that.
If