My marriage broke up last Christmas. My boys and I have been invited to spend Christmas with x-SIL (ex's sister). I have accepted. She and I have remained friendly and she thinks what her brother did to me was appalling - her ex had an affair too. She rang the other day to say to be at hers around 12 - fair enough. She then tells me that her other DB and SIL(my ex's B and his W) are going to be there for a pre-lunch drink (not staying for lunch) - fair enough it is her house and family.
AIBU to have said to her that we will come later when they have gone? Ex BIL and Ex SIL have not contacted me once since my H walked out on his family in April. I was told by friendly SIL that they wanted to see me and boys. They have shown me no support this year. I saw them briefly at nephews birthday party and they barely bothered to utter a few words to me. I feel if they want to see the boys they can contact my ex. I obviously don't matter to them.
AIBU and petty? SIL says she doesn't mind if I come later, just really don't want to spoil her Christmas. They are her family.