Hi Andrew,
Look into mindful eating. That means eating slowly, paying all of your attention to the act of eating. You'll end up eating less, enjoying it more, and gravitating towards foods that your body appreciates.
I have found this approach to be much more effective than willpower in changing my eating habits.
Here's a great post about how to test the waters with mindful eating, it's actually really easy but it will change the way you eat if you do it.
Your Mindful Eating Mission
He has other posts about mindful eating but this is a great place to start.