Hi, IntheProcess, and welcome to Psych Central! Do you think there might be psychological/emotional factors behind your eating patterns? It sounds to me like you might even be punishing yourself in a way.
See about getting your doc to prescribe you an antidepressant that's weight neutral. I am sorry to hear that Wellbutrin is not working out, since it fits into that category.
As far as just scarfing down snack food, I have started just eating non-sugary cereals such as Special K. I like the crunch and it's not too fattening. Maybe you can see about keeping such snacks around.
I hope you will feel better about yourself and be able to control your eating soon.