My family composition is similar and so is my food bill if I just buy what we fancy. Food has gone up a lot in price since coronavirus so anyone rolling their eyes at what you're spending is out of touch, I reckon. Eating some veggie meals is one thing but I don't recommend quorn or other meat substitutes as my experience of having my eldest, who is a strict vegetarian, home from uni atm is that special vegetarian food is massively overpriced (and also not very nice imo, if you look at what actually goes into it).
If you're all omnivores, that makes it way easier. The recipe book that changed my life is the Jamie Oliver Save With Jamie one, which uses a Sunday roast as the key meal of the week and then has a section for each type of meat full of recipes to make with the leftovers. I can easily get to Wednesday doing that and/or put some meat in the freezer for another time, and then finish the week out with veggie/beany/salad type things, something nice on Saturday and start again on Sunday. I have a huge stash of recipes torn out of mags, I don't just use the Jamie Oliver ones over and over. I basically try to make every meal go the distance for two or three days, using a few added ingredients. It saves on oven electricity too. I also use a slow cooker as you can use cheaper meat cuts for stews and curries that way and it's cheap to run.
If you can bring yourself to prep your own chicken, you can save a lot by jointing whole chickens into legs/wings/breasts etc, then freezing til needed, following the instructions in the same book. Part of what you're paying for is the labour that goes into it. I live near a port and also taught myself using youtube to gut and fillet fish so I could buy cheaply direct from the fishermen, but that's a bit niche probably. I also grow my own herbs and salad on the windowsill as that stuff is so overpriced.
Look at your receipts to see which outrageously priced things you're buying and try to find cheaper alternatives (e.g. own brands), make/grow it yourself (e.g. marmalade, hummus, pesto made out of wilty herbs), or just tell everyone they're going to have to live without it for a while (e.g. deli meats, posh cheeses). Puddings are massively cheaper if you make them yourself. A few cooking apples with a flour/sugar/butter crumble takes 10 minutes and costs practically nothing. Buy in bulk when things are on offer, except biscuits and chocolate, which never ends well. Farm eggs are way cheaper than supermarket eggs if there's anywhere near you, but check salmonella-free status (red dragon stamp) if you're pregnant. If you've got time to shop in person at different places, find out who sells what most cheaply, e.g. meat at the butcher, fresh fruit and veg from Tesco, bread from Aldi, or whatever. Price reductions usually happen at about 6pm.
Hope some of that helps.