I have the same problem, actually, and not even that seldom. I keep thinking about how I should finish up my chapters and update my fics before the readers will get sick and tired of waiting, but I just don't feel like writing
at all.
My solution? Same as already offered. I wait it out. I think it's better for your readers to have to wait a bit longer, than to make/let them read something you've forced out and may thus be not as good as you could have done at your best.
Just wait, relax, watch something nice, take your mind off things, maybe plan the story forward in your mind if you don't want to feel like a total slacker.
But don't fret, don't stress. Nowadays we stress way too much over so many things that it's getting silly. The story will come to you, sooner or later! And so will the mood. ;3