@Jennie75 I'm sorry this has happened to you, and I think the host is not the best, not to realize that the house wouldn't be ready and notify you earlier, especially with a large group and for Xmas.
In the future, it's always a good idea to keep up a regualr correspondence with a host after you book, rather than just book and not expect to communicate again until just before check-in. A message to the host a couple weeks, if possible, before booking "Hi XXX, looking forward to our trip and stay at your place, just making sure all is still on track with our booking." If the host doesn't respond in a timely fashion, that would be a huge red flag and you'd contact Airbnb at that point. Or it may prompt a responsible host to say "You know, Jennie, I'm actually stressed that the place won't be ready in time. We're running way behind schedule on the renos. If you want to book elsewhere, I'll give you a full refund."