On Xmas Day I found out my sister's and their children are getting together on NYE after I offered to host them. Me and my two children weren't invited, my sisters OH is on nightshift and she said she didn't want to be on her own with her two DD. I am a single parent so I felt they were being a bit thoughtless. For context we all live in the same town and have children around the same age. I told my sisters this upset me and now one of them isn't talking to me. She even removed herself from the family whatsapp.
The worst part is yesterday was my little boys birthday, I invited everyone around for cake and neither sister replied or came.
AIBU for feeling upset? I feel like I should never have said anything. I wouldn't have except my eldest is 10 and was present when we found out and was also hurt.