Depending on your interest in the science/art of aviation, before I pulled the plug on the whole thing, I think I'd give instructing a shot. That aspect retains all the parts of flying that it sounds like you enjoyed ... but it adds a dimension that only instructors really get a chance to see. If you have ever been interested in teaching or helping others to understand something, I'd give that a shot before going back to school and learning finance or something equally riveting. I won't guarantee that you'll like it ... but if you have an interest in flying and enjoy understanding why something is done the way it is done ... this may be a way to rekindle your interest -- of course, my background is training, teaching, and evaluating ... and there are few things in my career that I have enjoyed to the extent I have enjoyed that aspect. Before pursuing the challenge and excitement of marketing or sales ... I'd give pilot training a shot.