Don't quit your Coca Cola. I have a Pepsi Max addiction. I don't drink, I don't smoke, I don't do drugs, I don't go out a lot - I'm having my Pepsi Max! AND I'm having it in cans, so every drink is equally fizzy. You'll take it from my cold dead hands... you say you can afford what you are currently spending, but can see it's ridiculous - which is fine, but keep the things that give you joy.
Start cooking basic things that you can make in bulk and freeze. Chilli con carne is good - chop two onions and put in large pan, add two packs of lean beef mince and fry until the meat is all brown. Add 2 x Schwartz chilli spice packets, 2 x tins of chopped toms, 2 x tins of kidney beans, bring to the boil and then simmer very very gently for 15 mins so the flavours all combine. That would feed me and my husband for 3 large meals/4 smaller portions. If you can do that, you can also do spaghetti bolognese - and I'll often make them both at the same time, on a Sunday morning, so there's always something in the freezer.
Don't feel bad about using those tubs of microwave mash - they're easy if you need to get fed fast, and while mashed potatoes are easy to make in and of themselves, I used to get quite stressed trying to get the mash ready and dish up, all at the same time. I understand that if you don't cook regularly, it can be daunting.
But buying pre-chopped veg is a laziness too far. You can do that...
I know you say that eating with your husband is important, but I'd argue that eating with the whole family is more important. There have been loads of studies on the factors that lead to academic success in a child, and the biggest ones were reading for pleasure, having access to a computer and a desk just for them to work at, and sitting around the table for family meals. You can save money and set them up for life if you all eat together - and yes i know that creates a whole new set of menu problems, but you'd save time and money.