Remember that you shouldn't be going on a diet but rather, changing your lifestyle. Diets are short-term temporary fixes whereas lifestyle changes will help you keep the weight off for the rest of your life
What I did when I lost 10 pounds was at the end of the day I would eat a skinny cow ice cream bar. Sure, you could lose weight a lot faster if you don't indulge in treats but you may also lose your mind (which is why I allowed myself the treat everyday).
The rest of the time I would exercise 6 days a week (6 days cardio, 3 days weight training) and eat clean (ie whole grain, veggies, grilled meat). One ice cream bar a day didn't make much of a difference calorie-wise for me and I also did not feel as though I was being deprived. Maybe you and your wife could try something like that
Yep, some very good points here.
I like the idea of allowing yourself a sweet treat at the end of the day as a reward for sticking to your lifestyle change the rest of the day. Over the last year plus, I have gone through my own lifestyle change which has allowed me to lose over 30 lbs -- through much of what I describe above, which has included a lot of running and some calorie counting (with apps like "Couch to 5K" and "Daily Burn"). When calorie counting, I always made it a goal to leave at least 100 calories available at the end of the day for some sort of dessert, whether it was a serving of dry Chocolate Cheerios, or cut up fresh fruit.