Moomin, maybe you should stay motivated by saying "I will try my best every day to stay 100% and then I will reward myself once I have been to weigh-in regardless of the outcome by having smarties, because I already have the wake up of the weigh in to push me further the next week without punishing myself by denying myself the smarties". If you always have them to look forward to, use that as a motivation instead of punishing yourself when the scales dont say what you want, because there will always be some weeks where the scales dont say what you want them to, even when you have been 100%.