Well...... I will be the first to admit that sometimes it IS harder to eat healthy on a budget. But it can be done.
Fruits and veggies - buy in season if possible and local if possible. Look for farmer's markets and farm stands that may offer better produce cheaper than the grocery store. You may be able to find one close to work or even on your route to the grocery store. That way you wouldn't have to make a second trip.
Frozen veggies are also a good choice. Buy on sale and stock up on favorites. But watch out for the veggies with "added" sauces and flavorings. These add to the cost and they add CALORIES. Plain veggies are best. You can doctor them up at home if you so desire.
Meats - First of all, try consuming LESS meat. Try adding one or two (or more) non-meat meals to your week. Secondly, stock up with there is a great sale and use your freezer. If possible, package the meats into meal size portions. I put some of my meats right into marinade in a ziptop baggie and then into the freezer. They marinade when they defrost and are ready to grill or bake. Also, don't be afraid to buy meats on markdown (when they are near their "use by" date.) I buy nearly all of our meats that way and have never had a problem. Just be prepared to cook or freeze them within 24 hours.
Some of our meatless meals here include quiche (I make a regular one for the family and a "light"one for myself), baked potato night (I make a homemade cheese sauce and occasionally put out some homemade bacon bits, but just as a condiment... I also offer broccoli and meatless chili sometimes as a topping), pasta and sauce (who says you always need meatballs!), scrambled egg night, pizza night (no one really cares much for meat toppings so that is an easy one!), baked pasta with veggies (a recipe I modified to make it lighter), rice and beans with a fancy bread (bought from the day-old rack) or homemade biscuits, soups (lentil, vegetable, potato, broccoli).
Milk and dairy - Buy store brand (usually cheaper). Consume less. Not everyone needs a full glass of milk with EVERY meal. Cheese can be bought on sale or in bulk and frozen.
If you belong to Costco, Sam's Club, or BJ's, be sure that their prices are the best before you buy in bulk from them. I keep a price book and I try to remember to bring it with me. THat way I can know for sure whether I should buy that 10 pound hunk of meat!! The same goes for many other items. I am willing to buy 5 dozen eggs at once if the price is considerably better than the grocery store price (per dozen). And you have to KEEP checking, because prices change continually.
Well... I know most of what I said is pretty basic, but hopefully it gave you food for thought (no pun intended).......................P