As weird as this sounds it works for me. I PROMISED my treadmill and elliptical (and myself of course), that "if" I got on it I would stay on for my pre determined amount of time. Meaning, if I actually enter the room and get on the treadmill with my expectation of doing 30 minutes, I will.
Stop..STOP.. and make yourself a cup of your favorite tea. I like Vanilla Chai..the perfect combo of sweet and spice for me. I find that if I CAN just STOP and brew my tea..the sugary snack craving is gone.