John Michael Montgomery In Rehab

5/12/2008 Lisa Ann Schleipfer Country Music singer John Michael Montgomery checked himself into a rehab facility this past weekend, citing substance abuse due to anxiety attacks and a sleep disorder.  Montgomery has canceled all appearances and concerts for the next 30 days. "I will be disappearing for a while to try and defeat the demons that have stripped me of my energy of life and good health for so many years now. I assure you that however long it may take, I'm gonna fight to the end and come out stronger," he said in a statement Friday. Montgomery’s upcoming album, Time Flies, is scheduled for release in September 2008.