I'll go for one or two months at a time without writing anything maybe twice a year because I need time to recoop after various projects. During that time I always feel like I should be composing, but instead I "procrastinate" with other interests, and I get heavily involved in them. I generally don't stop playing an instrument, but I freeze up when it comes to composition. During this time I think "What's the point? Why do I bother when composition itself feels like a struggle, few people appreciate my music, and my prospects of living a financially stable life as a composer are slim? Maybe I'd be happier doing something else." Then I realize nothing makes me as happy as music. No, I did not say composition. Composition is, for me, a painful process. But the rewards of the final product are great: I get to discover and work with incredible performers (these are the people that truly motivate me), I get to see the work grow through rehearsals and possibly revisions, and there's nothing quite like hearing a freshly minted piece outside of my head and outside of Finale. It's thrilling. And music has this elusiveness and intrigue that doesn't compare to anything else I study; I feel like with each composition I'm working toward a better understanding of what music is or, at least, what it is to me.
I think most of us feel burnout at some point or another, and you might as well go with it and follow your other interests. It's important to take time away from the concerns of composition and just relax or discover new interests. If you aren't expanding your horizons and having new experiences, you're going to run out of things to write about. Oh, and go out dancing. Seriously.