Thanks a lot for your insight!

I don't know if there are other reasons - my relative works an incredibly high-performance job, so giving up their sheer energy might be a part of it - but the main thing they told me about was that they had overheard a young psychiatrist saying that any bipolar medication was "soul-crushing" and several other horrible things my relative has deeply, deeply internalized (and that I don't want to repeat). Frankly, I hope I never meet that man, for both our sake's...
Anyway, rebuilding that trust so that they can see there are new things to try would be a great step foreward, because right now they feel completely hopeless in part because of their (supposed) lack of options