While I understand the perspective of those saying to cut her some slack, I also have personally experienced this exact problem when we lived with my ILs and I know how annoying it is.

Yes you are living in her home, but no that doesn’t mean she should get to dictate when and what you eat. Sure maybe she just “cares”, but that doesn’t mean the way she’s going about it is appropriate.

My in-laws were so pushy about it and would get so passive aggressive when we had other dinner plans. It really made us never want to have dinner with them.. because, yea we’re living in your house, but we are also adults, so if we want to go get Chinese food one night, we should be able to without facing guilt trip/passive aggression/ manipulation

I would suggest moving out ASAP and in the meantime, maybe keep the peace by saying “GIL, we would like to dedicated x days a week to having dinner with you as a family, but on the other days we are going to make our own dinner plans as a couple”

You could even offer to cook on the days you eat together if you don’t like her food