Thanks for your replies. Unfortunately, I don't have a car and my mum and stepfather live a couple of hours away so I can't travel to get to them on Christmas day. In the end I decided not to go to see them on the day itself, and just stay home alone. I'm still going to meet them all with my son on Christmas eve though. A friend has invited me over on boxing day.

I just had a conversation with my mum and I could hear some kind of emotion in her voice when I explained my decision, which felt uncomfortable to be on the receiving end of - I don't know what specifically it was- a combination of things I think. She actually rang me because she said wanted to check that I wasn't becoming ill (because I had asked her why she had told me what my brother had said in the past yesterday) - I explained that I had been a bit fragile the past week, and she kept reiterating her concern that I was becoming ill.

I do think that her talking about me being or becoming ill has almost become a diagnosis when I try to talk about or address the dynamics of the family.

It did help to write out the situation - thanks for your comments.