Glad to hear you are taking control of your drinking and your back pain management. Also good to hear you are loosing some weight, that too will help with your back pain.
But please look into a proper diet and nutrition plan. One meal a day, especially of high fats and carb's, is not healthy and will only lead to more and bigger health problems down the road. Several small healthy meals and healthy snacks a day is much better for you. Like Magooch suggested eat lots of salads. Snack on things like fruits, nuts or carrot sticks to keep your blood sugar on an even keel threw out the day.
Avoid refined sugars. (Cookies, cakes, soda pop, white bread, etc,). They cause your blood sugar levels to spike and then dive erratically making you feel like crap. If you drink soda pop, cut back to one or two a day at most or quit entirely. I drink nothing but water during the day (and lots of it) and have one beer or glass of wine at dinner on the nights I'm home for dinner. I would rather not drink soda at all than drink diet soda. I am convinced that the artificial sweeteners that are used in diet sodas are toxic, and the large volume of corn sweetener used in regular soda is not much better.
Good luck Dale, and keep up the good work. Keep us informed on how you are doing.