This was one hell of an emotional roller coaster. I played the game from start to finish in basically one sitting once it really got rolling, and couldn't believe how much the game pulled at my heart strings.
After seeing the credits roll and sort of the happy feeling that I was left with, I got to thinking about the finale a little more, and it made me realize how awful things must have really been for River near the end. She spent all of her time trying to jostle Johnny's memories with those paper bunnies and carried that Platypus around everywhere, but she could never break through to him and passed on without him ever realizing who she really was. The doctors were able to put the pieces together for Johnny to die happily, but thinking about how painful it was for River is probably one of the most depressing things about the whole experience.