Having Bipolar disorder often leads to drug and alcohol addiction trying to cope with it, and also creates much more problems in dealing with other people on its own even without adding chemical dependency into the mix. It's a horrible condition to have, and even though I empathize with people who have it, in my experience they can also be incredibly difficult to be around because of their illness. Which is one of the reasons it's such a fucked up thing. It's self-perpetuating isolation.