I live near the coast. Actually, I live about 20 minutes from Gloucester, the setting for The Perfect Storm, the movie starring George Clooney. We can get some nasty weather inland, and even worse at sea. But if there's anything that us New Englanders are good at (besides voting for Kennedys), it's adapting to unexpected conditions.
Freelancing never brings consistent, dependable circumstances. App sales ebb and flow, clients pour in and then dry up, hits to the website come and go. The only thing you can predict about freelancing is the unpredictable nature of the work.
A key to surviving as a freelancer is to adapt and change as the circumstances change. When something unexpected happens, shift your methods and look for new ways to solve the new problems. Keep your eyes focused on the mission ahead, but bend and adapt the path to reaching that goal.
Staying the course can kill your business. Don't let your eyes leave your goal, but allow your feet to go where they need.