I've cried after exercising before, and before having to eat ONE MORE lousy salad, lol ! Because you get tired of it, and I think when you don't eat enough, you run out of serotonin in your brain, feel depressed, etc. Seeing a professional, either dietitian or counselor may help, or maybe not. A lot goes on when a person is overweight, it's not just about the food at all, the eating is what keeps us going.
Plan for tomorrow, but enjoy the heck out of today.