If we are doing something worthwhile, something that few others have attempted, we are bound to fail to meet our expectations and experience discouragement from time to time. If you know what you are trying to accomplish and have an idea of what you should do next, just keep going! Apply your mental resources towards solving the the problem, rather than reliving its bitter taste.
I am not the richest, smartest or most talented person in the world, but I succeed because I keep going and going and going.
If you're going through hell, keep going.