I do think there's an element of "meh" going on with me as well. I'm not entirely sure if that's all due to things tasting a bit off, feeling tired (I've been really upping my workouts lately), or if I'm just losing some of the joy from eating.
I'm sort of in the opposite boat in terms of food prep. I do almost all the food planning and shopping, as well as 90%+ of the cooking around my house. This is mostly because I'm retired and my wife is still working. When we were both still working, it was closer to 50/50.
I do think if I didn't feel obliged to make food for her, I probably wouldn't bother for myself.