Sugar seems to be my second biggest addiction. I ate a whole 100g chocolate bar in one go last night. That's a bit much even for me but I think I try to compensate for not drinking. Eating lots helps to keep the cravings at a minimum. And to be honest I don't think it does too much harm, no signs of overweight or diabetes.
I never experienced a sugar hangover though but I usually have a piece of chocolate first thing in the morning to get my blood sugar up. If I don't I can feel a bit nauseous (well now that you made me think about it, I can see some parallels to drinking). I can't imagine giving it up though, I always had a massive sweet tooth!