Hello Terry, And welcome to 3FC
I know compared to some of the other wonderful people on this site, I'm young and still learning ^_^ but i saw your post and really wanted to help.
First, before you diet, I think it would be best to talk to your doctor. Ask questions. are you are any medication that might need special attention while on the diet? are you lacking any sort of vitamin or mineral that you need to make sure you get enough of during the diet? Are you healthy enough for excercise once your pain starts to go away? Or can you do low impact work-outs? Like swimming?
About the food. I know what it's like to be afraid of food. That one wrong thing will throw the whole thing off. It's not true. You shouldn't ever be afraid of food. If you know what you're eating, what's good and bad about it, then you should no longer be afraid of it.
I believe in whole foods. fruits, veggies, grains, fish and meat. If you can go outside and get it right from nature, then its gonna be healthy. (some people stay away from red meat) If it's been turned into something else, then most likely it has added salt, fat, calories, and chemicals.
Calories are key. you need to find out how much you need to eat everyday. If you eat too much, you will gain...too little... and your body will think you're starving and hold on to the fat.
It takes a while for you to fnd the magic number, but just keep at it.
Diets that say, "only eat this kind of food" are not that great. for one, your limiting the vitamins and minerals and all other good stuff. Second, your body gets use to the same food day in and day out, and stops burning calories as fast. Plus you'll get bored with the same food and be more likely to stray off the beatten path so bad, just for a taste of something different, that you'll feel you could never save the diet.
It will be hard, but don't give up trying.