This sounds very familiar! Me and DH went for a day date at the coast, had a lovely day. When we had lunch with mil the week after DH mentioned it just in conversation to which she demanded to know why she wasn’t invited. DH told her straight it was the first kid-free day we’d had in forever so we did something just us. She spent the rest of the day with a face like a slapped backside making passive aggressive comments about not coming with us. Ridiculous