I'm sorry to read that you have back probs, might I suggest that you ask GP for physiotherapy in the form of hydrotherapy, aquarobics or something like that ? The water supports your weight and you can build up your muscles to help strengthen your back - just a suggestion.
I'm going to prove to you that you can eat well for less.
Firstly, you need to look at
www.dietdoctor.com/lchf as previously mentioned and make a note of the kind of real foods that you can eat like fish, meat, chicken, eggs, butter, nuts, vegetables, milk. Real food. Use that as your basic shopping list.
There's no reason why you can't eat canned or frozen fish, provided they aren't in carby sauces. Poundland has Fontinella wild pink salmon 213g £1 and Ocean Wave tuna flakes in brine 70g 3 for £1. Iceland has Young's Scottish kipper fillets with butter 170g £1. (If you don't have a freezer, just buy it the day before you want to eat it and let it defrost in the packaging, in the fridge). Poundstretcher has Princes Tuna Flakes 160g 49p and Oceans Best tuna flakes 3 x 165g for £1. Tesco sardines in oil or brine 120g, 40p. Tesco 6 frozen wild Alaskan salmon fillets 600g £5
Vegetables.. Amore Italiano canned peeled plum tomatoes 400g 25p each in Poundstretcher, Heinz canned chopped tomatoes 400g 3 for £1, Poundland. Oaklands fresh cherry tomatoes 250g 29p (offer), Lidl. Large flat mushrooms 250g, 59p, (offer), Aldi. Red bell pepper, 29p (offer), Lidl. If you have a freezer - Iceland frozen curly kale 1kg £1.50 Iceland frozen sprouts and bacon 600g £1 Iceland frozen ready to cook onions 650g £1.Iceland frozen broccoli florets 900g £1. Iceland frozen cauliflower florets £1,Iceland frozen sliced green beans £1 Tesco frozen sliced mixed peppers £1
Cheese.. full fat soft cheese, 200g, 49p, Aldi. Farm Vale mild white Cheddar 200g,£1, Iceland. (If you have a freezer, try and pick up some cheap yellow-stickered hard cheeses in supermarkets, and freeze for cooking).
Meat.. Birchwood Farm fresh pork belly slices 500g £2.15 (offer), Lidl. Birchwood Farm turkey drumstick 700g 1.99 (offer), Lidl. Iceland diced frozen beef steak 454g £2.50. If you have a freezer Grassingtons 6oz Angus Beef beef burgers 10 pack £10 so £1 each and 1.5g carbs per burger and 95% beef. Princes corned beef/reduced salt corned beef 340g £2 (offer). Tesco.
Eggs.. Iceland 10 Class A large eggs £1