GREY'S ANATOMY - &quot;What I Am&quot; - Addison doubts her abilities as a doctor, Cristina pushes Burke's rehabilitation, one of the interns suffers their own medical emergency, and Izzie receives the surprise of her life, on &quot;Grey's Anatomy,&quot; THURSDAY, OCTOBER 12 (9:00-10:01 p.m., ET) on the ABC Television Network. (ABC/GALE ADLER)PATRICK DEMPSEY