I used to attend group therapy, and a few of these folks would come by from time to time. Without exception, all were young women from middle-upper class families. While I'd never say it to them directly, they were much more like people with borderline personality disorder than they were like the folks who experience psychosis or more severe, debilitating, break-with-reality mental illnesses. That is to say, creative and more than a little bit attention seeking (whenever one came to the group, regardless of whatever else was going on with folks - including family deaths and close suicides - the meeting would always be about them and their alters). I never really bought it as anything more than identity politics inflected role playing, though I know they would hate that characterization.