I have been tempted on the odd occasion to slip over to the darkside myself when ive been feeling down, but always manage to pull myself out of it, I have a pack of wine gums in the cupboard which I have been desperate to eat, but they are still there.
I have heard that drinking water and a long walk can help bring sugars down so maybe try that, and next time you feel the urge try to think about how it will affect you later, this may help you to resist, though I know how you feel sometimes.