<p data-start="359" data-end="708">My best friend keeps disappearing for weeks, then comes back full of wild ideas and zero sleep. I used to think it was just their &ldquo;creative phase,&rdquo; but now I&rsquo;m worried it might be something deeper. Can you suggest resources on <em data-start="632" data-end="682">bipolar disorder in the US: symptoms & treatment so I don&rsquo;t feel clueless?