There's some wonderful things about being stuck with your writing. It could be an opportunity to try your hand and writing other things. There's not just one genre or one story out there after all and as much as you may love that genre or that story sometimes I'm learning they just need to sit and stew until you find out what's wrong with them. That sometimes means writing other genres, trying other things or reading, reading, reading every writing book you can get your hands on.
Most of all when you're stuck just don't stop writing. Write anything else, free write what you're stuck on, anything but stopping. When you stop it dies, that's the problem... let your love of writing shine through and guide your words even when what you want to work on is stuck. Just always go back to what you're working on or you'll eventually start tons of projects and never finish them. With writing finishing the project is almost more important than starting them.