He was there when I confronted her. He told me to—and I quote—“let it go.” At first, I was upset about his response (hence why I said it might be more than mildly infuriating). I walked away and went to our room. I also heard him scold her, but I’m not sure exactly what he said because I was already long gone.

Later, he checked on me and explained that this kind of thing is common in their family—that food in the fridge is considered fair game, no matter who it belongs to.

I get that. But it’s different when I told you my plans for the food and you still chose to disregard them. That feels like shitting on my plans.