Bipolar is when you travel to the Balkans, visit Kosovo, talk to a ghost in your room of your guesthouse and don't question anything about it. (also when you meet a waiter in kebab place who has scar on his face and you wonder if he fought in the KLA and you don't find it scary.... )

(or wait. Maybe that's just the Balkans. Maybe there is something in the (rather scarce) water there)