A bit of background. We met at work and have been friends for over 12 years. Both divorced and single. We holiday together and attend the theatre, cinema and local cultural events together. Every Christmas we meet up with two ex-colleague's for pantomime, lunch and exchange gifts. This year I didn't fancy the the panto and neither did the two ex - colleagues. My friend suggested we just meet for lunch and exchange gifts. I said I was up for that and would invite the others. However, the others said they had lots on in December and would rather leave it to January and I agreed as I was also very busy. I told my friend via WhatsApp (our usual communication method) but she didn't respond. On Christmas eve I sent her a Christmas greeting and wished her a lovely Christmas. I received a curt "thanks". She has ignored my suggestions for theatre visits and all attempts to engage with her. I have asked her if I have done something to upset her but she hasn't responded. I know she isn't ill because she posts on social media daily! AIBU to think she is being childish?