We are also on a tight budget, so this is what we do:
1) buy whatever meat is on special each week and freeze it; every store has 1-2 cuts on really cheap each week; stock up.
2) buy BONELESS meat on sale whenever you can; you save half the cost simple becuz you aren't paying for the bone weight.
3) buy cheaper cuts like blade or crossrib steak/roast instead of rump; chicken legs instead of breasts (except when they are in sale); or a whole chicken and make soup out of the carcass; pork roast or picnic hams; turkey when it comes on sale and freeze the leftovers for sandwiches or more meals.
4) add lentils (dried split peas of many colors) in your chicken or beef stews or soups; this adds cheap protein and stretches the chicken. I often grab chicken legs on sale and make a stew or soup with dumplings & veggies.
5) buy a ham, or a beef, or pork roast on sale; use leftovers to make casseroles and soups or cottage pie to freeze.
6) make pasta or rice casseroles; add dried beans and/or lentils and cheaper veggies like carrots, peas, etc to stretch them.
7) cabbages, carrots, onions, celery, and turnips are often cheaper than other veggies and go a long way to flavor soups and stews too; some veggies are on sale each week; stick to the seasonal stuff, especially in the fall when fresh farmer's produce is send to the stores in baskets and bags (we clean'em and bag'em and freeze'em or store'em for the winter).
8) buy frozen veggies when fresh are too expensive; watch for sales.
9) go to farmer's markets where meat and veggies can be bought for less; and don't forget department stores sometimes have many foods for less.
10) make your own EZ biscuits, scones, flatbreads, no-knead breads/buns, pancakes, and muffins, which are cheaper than buying bread for a family. (use baking soda instead of baking powder; it's much cheaper).
11) I grow green and yellow beans, carrots, onion sets, and summer turnips in dryer drums and large pails or bins; you don't have to have a garden -- even a box or pail will do; try it and you'll see. YOu can grow radishes, spinach, leaf & romaine lettuce, parsley and chives in them too. Start and make just one small garden the size of a box; and add one each year.
12) buy from local farmers; at the end of season, we have farmers that will give away veggies for FREE -- you just have to go pick them; so we clean them and pack in baggies and freeze them for winter.
13) add in a few vegetarian meals each week; you'll save on those, so you'll have more $$$ for better meat cuts and veggies.
14) The Hillbilly Housewife has menus for very low cost recipes on her site --
www.hillbillyhousewife.com/40dollarmenu.htm
We have a thread here for Physical Challenges in the Dieting with Obstacles forum. We have people there recovering and living with challenges and limited incomes (myself included). I do chair aerobics; use stretchie bands (or just use a stretchie piece of material like terry); hand weights (you can use cans); do toning exercises lying down on my bed or couch: tummy tucks, leg lifts, etc); lite yoga, tai chai, or pilates; dancing; swimming; walking, etc. Where there's a will -- there's a way ...