How do you motivate yourself after a bad day?

I take a deep breath. Walk my dogs, and try to move on. Try to remember that it's only a couple of days, it won't undo everything you've worked for. In a few weeks or months if you stick to your plan it won't make much of a difference. Don't panic, try not to punish yourself with loads of excercise and starving yourself. You cannot hate yourself into being healthy.