Simple actually. Dump the cravings, whether they be alcohol, cigarettes or (in your case) sweets, it is all the same. Tell yourself you can do it BUT KNOW that within a month or so (even weeks) you will feel better. Plan for that.
Know that it will do you good and as each day passes, It will become a lot easier. Discipline (always) and remember if you can, what you were, where you are and appreciate the difference that YOU make . Dig deep, give it your best shot and let us know how you're getting on.
Reckon with some serious work for over a week, you will not believe the change. Go do it. Emulate what many on here have done and have changed their life around and don't tell me you can't when I know you can. Prefer a few weeks hard work than something far worse down the line. Up to your good self, but I've got your back should you ever need it so don't think I'm bowing out on you.