PRIVATE PRACTICE - "I'm Fine" - During a dark moment in his life, Sheldon finds happiness with a new woman. Meanwhile, he becomes increasingly suspicious about his patient Nick's involvement in Sarah's disappearance, on "Private Practice," TUESDAY, DECEMBER 11 (10:00-11:00 p.m., ET) on the ABC Television Network. (ABC/ADAM TAYLOR) BRIAN BENBEN, MATT LONG