"You realize that River knows what's about to happen to him. She knows Eleven is near his end & she's saying goodbye, not just to the Doctor, but to HER Doctor, the one who was there her whole life, who loved her and saved her. And I think she's also saying our goodbye for us. Matt: How do I say goodbye? Whovians: Say it like you're going to come back. Matt: Well then. See you around. Whovians: Until the next time, Doctor."