This year we are doing Christmas at my sisters, which is a small cottage in a remote location (highlands of Scotland remote).
We usually end up with a few waifs and strays and have ended up with more than usual. So we have Booked cabs for those from a nearby town to go home in the evening and those from other remote villages who will struggle if they have been drinking to get home can stay.
One of the people coming is from the town, and is a friend of my sisters and is an Aussie who can't get come for Christmas, she lives nearby my mums brother. Excellent.
Also nearby is a girl me and my sister went to school with, who has sort of guilt tripped us into having her, she has family to spend it with but she had a minor argument with one of them 89472 years ago so doesn't want to see them... Initially she asked me if she could come and I said id need to speak to my sister it's her house etc, she got cross saying we'd invited som random Aussie but not her, an old friend etc. My sister said sod it for the sake of keeping the peace well have her.
However she is continuing to be difficult, I was going to pick up her, my uncle and the other girl from the town where they all live at noon after my uncle would have been to church.
She has turned round and said well she is going out on Xmas eve and might not be awake By then and maybe wants to see her family so she'll let me know on the day when I can come and get her. 
and we can have dinner when she gets there... More
Then there was the kick off when she couldn't stay... There is a cab booked and paid for and literally NO room in the house. Again apparently it's unfair
AIBU to say she's getting picked up at noon. We are having dinner when we are having dinner and no she really can't stay there is NO ROOM.
She's 30odd ffs 