Question for those are already into fitness prior to cruising

What do you do to stay motivated? And how do you deal with diet? My husband and I started our P09X3 program Labor Day weekend because we want to get our old bodies back. We are now closing in on our third block, and I have to say I am not happy with the results. The program itself is fine, but it's the diet I am struggling with.

I am currently going by the book provided in the program. All the foods you can have are placed into categories (carbs, healthy fats, proteins, etc.), with the 'better for you foods' listed towards the top of each category. You select your foods based on how many of each category you should be eating at each meal. For example, breakfast is 2 proteins, 3 carbs, 1 fat. Oddly enough, veggies are placed into the carbs category. So my typical breakfast will be egg whites with spinach, mushrooms, tomatoes, avocado, and a glass of milk.

I stay all of this to show I follow the guide pretty well, but I am not seeing the results I want. I've lost MAYBE 10 lbs. For closing in on a 90 day program, I am expecting to see a bigger loss. It's really discouraging. I plan on completing the program and will go back to the original P90X program. In the meantime, what motivations do you guys use/do in order to stay on track?