I think there's a couple of things going on here where you could make life a lot easier for yourself
Plan your weeks meals & ensure that for at least 2 if not 3 meals you can double cook & have it 2 nights in a row. Things like beef stew, mild chicken & veg curry, chicken pie, cottage pie, bolognaise, fish pie, chicken casserole, mild chilli, lasagne etc
Serve dc theirs at 5pm & have yours & dhs ready to heat up whenever you're ready to eat
Share the cooking with your dh. He should be cooking a couple of nights a week
Build up a stock of small portions of dinners your dc will eat & freeze them. That way you have a quick hassle free proper dinner for them. Freeing you & dh up to have something you enjoy from time to time - a spicier dish, a takeaway or a supermarket ready meal deal etc
Focus on your own health & prioritise that. Even at 5ft 10" at 16 stone you're overweight & I'm sure you know that. You will feel better & have more energy if you tackle that & start eating healthily & properly. And it's a far better example for your dc too.
This doesn't mean starve yourself. It means being mindful to eat 3 proper nutritious meals each day. They can be v simple. I have lost 2.5 stones this year & generally only by eating mindfully & healthily. No fad diets.
A general I have weetabix for breakfast.
Soup for lunch. Either supermarket fresh tub or canteen in work or at least once a week I roast all the left over veg in the fridge &,add herbs & spices & stock & blend- gives us lunches for 2 or 3 days. I have mine with brown soda bread & real butter.
Dinner is something like fish, steamed potatoes with butter & salt & pepper & peas; or chicken & veg Curry - rice & naan for dh & dc, cauliflower rice for me; caesar salad kit from supermarket. Add extra such as tomato, Avocado, chicken or ham or hard boiled egg. Sparing on t by the dressing
Roast veg with herby chicken- one tray pan roast etc
Good luck!