One thing you might want to check out is what/how much you're eating every day. I know I have problems when I eat less than what makes me feel full. For that reason, I switched to a healthier eating plan and so can eat a lot. Also, I make sure to treat myself once in a while (have a sandwich with white bread and beef - delicious!), and that helps me to not go overboard with bad foods.
Also, try to keep the unhealthy foods away from you. Out of sight, out of mind really does apply.
Good luck! You can do it!