I think one of the key benefits of strategic living is the space and time to be useful. To be confident you're providing value to someone, somewhere, at another time.
But you need time to be useless - to do things just for you, to not worry about who you're trying to please or help. It's also a matter of ego: the world doesn't depend on you for happiness. It'll find it, or not. But that's its problem.
For now, just play that song. Listen to music. Watch that TV show. Relax. Tomorrow is another day to work.
(For more thoughts on this topic, read Derek Siver's essay, "Art is useless, and so am I.")