Well, there are medical issue for weight gain aside from just over-eating. I'm one to talk because I've been overweight and I give it to anyone who's properly maintaining their weight and has very low metabolism. It took me a while to get into to workout routine and watch my portions so I don't hold it against anyone for being large. One of the hardest things to do both physically and emotionally is lose a lot of weight. There have been studies done that for people who over-eat food has the same affect on the brain as cocaine.
Quite similar to working in sales. An old friend of mine and I came to the conclusion that the sales cycle is a lot like what a drug addict experiences (insert food, adrenaline junkies, etc. for the word drug). You search and search for the next client (drug), get rejected, abandoned, etc. and then you make a sale and feel elated, and then the cycle repeats. PErhaps a sales group similar to the 12 step program might be useful.