Sorry you are upset about the arrangements but Christmas is only another day ....you have 364 other days to enjoy with your family and a weekend in Spring where you could enjoy time out with your GC would be wonderful ! Personally I prefer Christmas alone ...each to his own ! My ex H's family were east enders and talk about OTT ! My present husband hates Christmas so he will be in one room and me in another ! Here in France Christmas day is just like any other. Families get together maybe on Christmas eve ,,,,we even had a workman turn up on Christmas day once to start concreting the paths !
You could buy a fold up Z bed (ebay) or a blow up mattress ...so if they say they have no room...hey ho ! sorted ! or you could try Airbnb near the flat ,,you might find someone else on their own who would love to have company....or ask your Salvation Army or Church if they know of any lonely old folk you could visit or somewhere you could help out !
The Christmasses I spent on my own did not bother me at all ,,,but as someone said, everyone is different ! for instance my brother who has always been single used to love his Christmas day off so he would chose to stay in bed until late then get up and watch tv ,,,,,this is what he looked forward to all year ! Normally he was up at 5.30 and off to work !
I would be careful what you say ,,,you might alienate them altogether whereas this way you will get to see your GC sometime ,,,,and think they may one day emigrate to Australia !