Miley Cyrus is opening up to fans about her struggles with mental health--even if that means doing so in the middle of a performance.Over the past few years, a growing number of celebrities have become more and more honest about depression, anxiety, and other mental health struggles, but we’ve never seen a huge star like Miley discuss it, in real time, on stage. At Summerfest last month, the former Hannah Montana actress confessed to a packed crowd that she thought she was about to have a panic