*With details: Meal planning for couples when one is on a low cal diet and the other is on a high cal diet?

Any meal consisting of lean protein and veggies should be fine. You can add some carbs as a side for your spouse, while you consume mostly veggies (maybe even add a side salad for yourself) and you two can both consume whatever lean protein (meat, beans, or whatever you prepared). Find some veggies he likes, because living on nothing but protein and carbs, is not healthy for him. There are too many nutrients the body needs that it can't from just those 2 things.

The protein part should be easy. Something you both like that's healthy. Then simply work out the side dishes based on what you each need and prefer. You can always add a salad to your meal, if you want more bulk without adding a lot of calories (just watch the toppings/dressing). He can get carbs from having brown rice or whole grain bread or some other carb as a side, that you may want to skip or eat only a small portion.

You eat portions that suit your desired calorie intake, and he does the same.

I really like the food advice articles on the SHAPE magazine website, I'm sure there are other resources out there too. Have you tried using protein powder shakes for him? Also random, but have you tried specific diets such as Paleo or Gluten Free for you?