When Katy Perry was chosen as one of Barbara Walters' 10 Most Fascinating People of 2011, it should have been an honor. Instead, the "Dark Horse" singer was petrified that the esteemed journalist would discover her marriage to Russell Brand was on the rocks... I was just exhausted and stressed." "I'd prepped everyone that I was running late, but Barbara showed up at the original time anyway," the singer continues. "When I got there, I apologized immediately, but then she said to me, 'You know, I've only ever waited for one other person this long, and you know who that...