I will admit I haven't read all of the replies, so sorry if this is a repeat.......
Add stuff to fill out the meat if you are using a ground meat (ground beef, ground turkey)... roasted chopped mushrooms, shredded zucchini (and other veggies), rehydrated TVP (textured vegetable protein), brown rice, mashed beans.
I made sloppy joes last night that had TVP, mushrooms, and carrot pulp (from making carrot juice) and it was delicious, cheaper (especially since the carrot pulp would otherwise go in the composter) and healthier.
Make "less meat" meals like stews and double the veggies without doubling the meat portions.... like beef stew with just a pound of beef.... but double the carrots, onions, and potatoes. Beef stew and curried chicken stew are two big favorites in my house.
Fried rice is a great way to use lots of (cheap) brown rice, healthy veggies, and just a bit of meat and egg! Sometimes if I have just a bit of ham or chicken or beef leftover from a meal, I chop it small and freeze it specifically to save for fried rice (or in my household, fried "cauliflower" rice).
Stir-fry.... and you AGAIN can double the veggie portions but not the meat.
Enchiladas, quesedillas, stuffed shells.... all of those have a meat FILLING, but use very little meat per portion... especially when you use veggies along with the meat. One of our family favorites is "skinny chicken enchiladas" and "chicken salad stuffed shells" (you could probably google these recipes).
Soups!! Lots of veggies and broth to fill the bellies and just enough meat to taste! Actually, my family's two favorite soups are meat-free.... light broccoli cheddar (served in a homemade bread bowl occasionally) and curried carrot (served with a side of sliced cheese for some protein).
Whatever you do, try to limit those meals that are essentially a "slab" of meat per person (whole chicken breast, whole hamburger, whole steak, whole pork chop). Best of luck...................P