Here are a few ideas to help you get started (or continue) eating healthy on a budget:
1 - Cook beans from scratch & use them in lots of different meals. Beans are nutritious & filling, but it gets pricey to buy them in a can. A pound of dry beans usually sells for $2 or less, and a big pot of beans can add significantly to the weekly menu plan.
2 - Make a weekly (or monthly) menu plan. I don't know about you, but if we wait until we're hungry, then we end up eating whatever is quick & easy to prepare, which isn't always what's cheapest. Planning ahead allows me to choose a healthy variety of foods and save money in the process. Another way meal planning can help save money is that I don't buy things that sound good only to have them go bad because we're busy using up all those other things I bought because THEY sounded good, too. ;)
3 - Make broth! Save the bones from all the meats you eat. Put them in a container or bag in the freezer if you don't have very many at a time. When you have a decent amount (like the bones from a whole chicken, or a few roasts, etc.), then put them in the crock pot, fill the crock pot with water, and turn it on low for 24 hours or so. Bone broths made this way extract the gelatin & other nutrients from the bones, which greatly enhances the nutrition of any diet. Did you know that the amino acid profile of gelatin perfectly complements that of the muscle meats? What one is missing, the other has - in perfect balance. Consuming broth made in this way has a protein-sparing effect, making our bodies happy with less meat than we might otherwise need to be satisfied.
4 - Buy a crock pot. If you don't have one, it's well worth the $20 or $30 investment, even if broth is the only thing you ever use it for!
5 - Ditch the microwave. It changes the actual molecular structure of the food, rather than just making it hotter, which means that the foods aren't what your body is expecting from nature. Try a toaster oven for reheating leftovers or preparing something small. It takes some adjustment in getting used to things taking a bit longer, but there's no sense in damaging the food you worked so hard to afford & prepare.