Grey's Anatomy Rundown: Episode 18, "Stand By Me" When something horrible happens to you, do you stare it down? Or do you run away? That's the question on this week's Grey's Anatomy, as Izzie deals with her diagnosis and Derek remains in the woods, unable to face the hospital where his last mistake took a life. I loved the way this episode brings the characters together in botched but earnest efforts to support each other. Ready to talk about it?