I agree. I think it is the rare sponsor who would do something like that, and not a good reason not to go back. There are doctors who shouldn't be practicing, too, but most of us do not give up on the entire medical profession.
Let's face it, though, in addition to what your sponsor did to let you down, YOU were not working the program--you were drinking in secret and lying to everyone. So you really can't judge how effective it would be if you really WORKED it.
It's your right to continue to be miserable if you want to, but it sure seems worth doing what you can to change that.