I think it may be the ambien causing the binges!! I binged when on that med., and since I have stopped, I no longer have this. Try quitting ambien and see if it makes some difference!
You are certainly engaged in a very unhealthy habit. It is dangerous to do this over a period of time even if it is only once a day. The real issue is your obsession with food and weight and you can do something about that. This kind of a session is really a mental block and interferes with your personal growth and development unless you do something about it. You can seek therapy for it or you can go to a self-help therapy program like I have designed called shrinkyourself.com. There you can read about others who have conquered the succession and decide whether or not you want to expend the effort to do with the source of your problems at this time.