So as far as I know, no one else in my family has it, though both sides of my family are pretty conservative/formal and don't talk about things like that.

My dads side seems normal. My moms side is where I think things come from. On her side, I have an uncle with alcohol problems and his son (my cousin) is currently having issues with holding down jobs and fighting with parents/leaving home.

My mom was depressed for a period of time, but that was more situational because my brother and I were shitheads as teenagers. My brother has been severely depressed for years after a lot of substance abuse in his late teens/early 20s.

The fact that no one in my family is diagnosed is one of the biggest reasons I doubt myself and think I'm making it up/projecting symptoms onto myself.

I just remind myself that I had no idea what bipolar actually was when my psychologist first brought it up to me, and I cried when I searched it online because it was so similar to what I'd been saying in the sessions.

And I don't have any environmental factors except drugs pretty much.

I reaaally want to do one of those genetic tests to have something tangible that says it likely is (or isn't by some miracle) bipolar. Did you just do 23andme?