This sounds reminiscent of my own experiences (three plus years dealing with an as yet undiagnosed condition(s)). Regarding your first point, the most useful th

This sounds reminiscent of my own experiences (three plus years dealing with an as yet undiagnosed condition(s)). Regarding your first point, the most useful thing for me was finding a doctor I work well with - being able to suggest a potential cause/treatment without it coming across as "I'm the patient; I/The Internet know best" has been extremely useful. Most of the time I've overlooked something (I'll never have the same knowledge/experience base as my GP), but the few cases where it was relevant and hadn't occurred to my GP have lead to better treatments.