This is a very good post and echoes my experience. I consider myself a smart person and fell head first into the "if only I was a pure raw vegan/fruitarian" mindset for at least a couple of years. All it got me was spending tons of money and energy on food, having it be the central focus of my life, losing a lot of weight (muscle and fat) and denying myself foods for what I see now as a false reason. I would have been just as good, if not better, eating a semi-healthy version of SAD as I was trying to be a fruitarian or near fruitarian raw vegan.
I had much the same experience. I would go through numerous diets such as cooked palaeo or raw vegan/fruitarian and then primal diet, wondering if there was some perfect fruit or (cooked) wildgame meat that would help me overcome my health-problems. The trouble was that, at the time, info on diet, especially raw-meat-oriented, was virtually nonexistent online.