Play less, have other interests besides MMO's, and make time for them. There you go, no burnout.

Most MMO's aren't friendly to being played less, so people keep playing when they really should shelve it for a month or more like any other game. Of course you are going to burn out on something you may have spent 6 months playing in real-time, or that you play more than you would work if it were a job instead of an MMO.

It has to be worse for you, because you have to write about them in addition to playing. For me lately I've made a conscious effort to play less, and I avoid endgame now simply because I don't want to spend an entire evening playing the game.