I feel your pain!!
I am exactly the same. I cannot stick to a diet for the life of me. I started a thread on here back in january with the hope to lose 10kg, and its now march, and i'm still the same weight.
But I am finding that the harder I try, the more I stuff up. When I dont worry about "dieting" as such, i eat rather healthily, and exercise. Its very weird. But when I know I cant eat "bad" food, i pig out and binge.
I find keeping a food diary really helps. That way you can track what you are eating!