She feeds her family on $40 a week and writes about how she does it on her blog, frugaldivorcedliz.blogspot.com.
She buys in bulk whenever she has extra money and stockpiles staples such as oatmeal, cereal and dried beans.
Feeding her children healthful food is a priority for Nelson, and it's something she's unwilling to compromise on.
"I always think that my economic straits aren't going to last forever," she said. "I don't want them to not grow up healthy because of my divorce."
Nelson makes many dishes from scratch, including snacks such as granola bars, and she keeps her meals simple, which helps her save money.
Processed convenience foods rarely make it into her grocery cart.
"It takes a lot more time to cook from scratch," she said. "You have to be willing to plan ahead."
Many of her meal plans, which she posts on her blog, contain just three items: a main dish, a vegetable and a bread.
"Luckily, my kids like simple food," she said.
Whenever she has a little extra money, she uses it to stockpile foods for those meal plans.
Nelson tries to plan treats and desserts to keep from feeling burdened by her limited grocery budget.
Coupons and grocery sales help her save 5 to 10 percent on her grocery bill.
Frugality isn't limited to the kitchen. It's a lifestyle Nelson enjoys. She stocks her purse with snack foods to fend off temptation in the school cafeteria, buys books and movies at Goodwill, and makes her own laundry soap and cleaning supplies.
"If I want to buy something," she said, "I ask myself if I really need to buy it."
Coupons can clip a lot off grocery bills
Karen Green lives by coupons.
Because she uses them diligently and matches them with grocery sales, she consistently saves 60 to 70 percent off her grocery bill.
She teaches her technique to others through a monthly couponing column in North Augusta Today and through classes at Chicks University at The Family Y in North Augusta.
"It takes awhile," she said. "You can't do it all at first."
An infomercial 18 years ago about using coupons grabbed her interest, and she's been doing it ever since.
It takes a month to six weeks or so to for using coupons to really start saving money, because you have to go through a few sales cycles, she said.
Green spends about 90 minutes a week clipping coupons and matching them to sales fliers.
She said she spends about $150 a month to feed her family.
"I don't budget it out because I buy from sales and coupons," she said. "I have a stockpile of food."
She stores food on shelves in the basement, in a chest freezer and in two refrigerators.
She develops menus based on what meats are on sale and the groceries she has on hand.
The first step in coupons is to gather them, as many as possible Get people to save them for you. Set up a second e-mail address just for coupons. Sign up for grocery store loyalty cards.
Set up a filing system for all of them, even if it's just envelopes. Then match the coupons to sales fliers.
Green recommends that beginner sshould start with the store they most frequently shop .
Her philosophy is to never pay full price for anything.
"It's really a matter of retraining your mind to get out of the mind-set of 'I have to have it now,' " she said. "If you need it and you don't have a coupon for it, find the cheapest price."
Dietitian stresses nutritional value of foods
For Candace Stapleton, a registered dietitian for University Hospital, eating healthfully on a tight budget is absolutely doable if you eat according to portion size.
"Take a typical can of Campbell's soup," she said. "That's really 21/2 servings in one can."
Cooking at home is best for eating healthfully and inexpensively, because you can control the ingredients in a dish.
"You may have to use a higher-fat (cut of meat), but you can control what else goes in there," she said.
Choose reduced-fat versions of the other ingredients, which are often the same price as the regular variety.
Unless salt is essential to the structure of the dish, such as baked goods, don't add table salt to dishes. Flavor them with herbs and spices that do not contain salt.
Stapleton recommends staying away from convenience foods as much as possible. Many of them are loaded with fat and sodium and can sometimes end up being more expensive in the long run.
Toaster pastries, for example, come eight in a box and are packaged by twos. They will last for only four meals, Stapleton said.
Instead, you could buy a dozen eggs, store-brand cheese and a loaf of bread and make egg and cheese sandwiches.
"You may spend 50 cents more, but it's going to last a lot longer," she said.
She suggests shopping for frozen fruits and vegetables.
Fresh is best, but frozen is a close second in nutritional value. Canned is OK but contains sodium as a preservative.
"If canned (vegetables) is all you can afford and you can't get the low-sodium variety, drain them and rinse them before using them," Stapleton said.
Planning ahead is key to eating healthfully on a budget. It takes preparation and commitment.
"Healthy is a lifestyle," she said. "It's not a diet. It's not a fad."