Are you under any unusual stress this year ? stress can cause a person to eat for comfort when they really don't want to eat. It's also possible that your low carb intake may be too low and that might be the reason your body is craving sugar. Are you eating enough ? Eating too little during the day in a quest to be "good" can set us up for failure later. So, do make sure you're eating enough during the day so that you don't feel hungry later.
Are you having enough healthy snacks ? When you feel an urge to go for a treat, how about having a piece of fruit instead ? The natural sweetness of the fruit, plus the added fiber should help keep your blood sugar levels stable so that you don't feel an urge to over eat.
Not to get nosy, but is it TOM ? Many women do tend to have cravings for sugary treats around the time of their menstrual cycle. So, it's also possible some of your cravings could be PMS related.
These are just educated guesses. Because we're all different why one person feels a need to over eat will be different from someone else.
What to do ? Try having a piece of fruit or some other healthy snack. If you think the candy is too sweet, that really is a signal to stop and think about WHY it is you feel an urge to keep eating. And yes, there really is a reason why we keep eating. We might not like the answer, but there is always an answer.
just a few thoughts.