Sometimes the best thing you can do for a WIP is close the file and stay away from it for a while. I decided to do that, but I didn't want to stop writing. It's been a long time since I wrote something purely for fun, with no thought toward submission and possible publication. I tumbled on an idea and ran with it, having fun telling a story and not worrying about length or rules or anything. I started over the weekend and by Thursday afternoon had ten thousand words, the same amount it took me weeks to reach on the WIP.
I don't know how long this story will be, though I am sure it won't be a full length novel. I have no idea what I'll do with it when it's finished. I just know that right now I'm rediscovering the sheer joy of storytelling, and I'm loving every page of it. Stress and pressure can rob you of the fun of writing. It's important to let go of that and write something that reminds you of why you're a writer in the first place.