I can totally relate to the doubting and wanting to know for SURE. I have been diagnosed by at least 5 different doctors over the past 10 years and I still don't believe it half the time and thus am basically unmedicated (I also have health anxiety so I'll be damned if I'm going to take something with horrible side effects if I don't absolutely need it!).

That said, remember that bipolar is on a spectrum. I once read something that stated the question as: "it's not whether you're bipolar or not, but how bipolar you are" - e.g., where are you on a scale from classic unipolar depression all the way to depression with mania and psychosis. Somehow it's possible for me to accept that I am on the spectrum (and not at the far end of unipolar depression), yet I can't fully buy into the idea that I have BP. It's rather illogical, but it's as close as I can get at the moment.

(I highly recommend the website psycheducation dot org)

as far as medication, I am not the person to give any sort of words of wisdom whatsoever, but I can tell you that I relate and I think this is very common amongst people with BP