Let's say you're in a committed relationship and you both decide to eat a bit healthier. You've spent years eating chips and cookies, and now you're ready to switch to fruits and veggies.

Making a 100% switch can be rather challenging, even with each other as motivational forces. So allow a few indulgences. It's okay to have an ice cream sundae or milk shake every now and then if it means you'll stick to the diet over the long haul.

So get into healthier eating as a couple but be realistic. You'll improve your chances of success and not feel so guilty when you eat some ice cream here and there.