You might try to make meals with enough leftovers that you can freeze the extras for the days you are struggling.
I also discovered the world of frozen veggies while pregnant and it made my life easier. You can make lots of variations with mininal effort using the pre-cut veggies... stirfry, curry, stews, soup, casserole, and "pot pie". I would also alter canned soups, such as adding frozen potatoes, peas & carrots, green beans, and seitan to butternut squash soup. I try to keep a varied diet, part of it is eating at least 5 different veggies per meals.
Another favorite: Anything on top of a baked potato. Variation 1. Canned black beans (rinse before cooking) with onions, garlic, mushrooms, and canned or fresh tomatoes; heart of romaine lettuce, black olives, avocado, salsa and some cheese (cheddar, jack, or even cream cheese).
Variation 2. Canned lentils (rinse before cooking) with garam masala (cooking spice- could use curry powder, too), onion, carrots, green beans, peas, and garlic. Top with coconut milk and raw cashews.
Both of these also go great over rice.