The idea that you play chess, even if you don't enjoy it, was first pointed out to me in a book by Reuben Fine that chronicled the lives of the worlds leading players throughout history. Salo Flohr was one of the leading players in the 1930's, but according to Fine, once he reached to top he felt the need to protect his reputation rather than strive for the ultimate prize. As a result he began to play risk free chess, which resulted in fewer losses, but fewer wins as well. And while there was an argument that he could have played in the 1948 World Championship tournament (as a surviving participant of the 1938 AVRO event), he was replaced by Vasilly Smyslov. I can remember thinking at the time that this was a little sad that a promising career was curtailed by the necessity to make a living.
Of course the alternative is to do a Morphy or Fischer and just quit, or even a Lasker, taking long breaks from the game. At least in the case of Anand, his lack of passion for the game did not last that long, and he seems the better player for it.