I didn't want to let things go too long, so I figured I'd just toss out a brief post here, and (hopefully) give you some words of inspiration. I picked up the most recent issue (Summer 2006) of Written By, the WGA West magazine. In the editor's opening note, I read the following line:
Or google psychotherapist Dr. Robert Maurer's behavioral studies demonstrating that successful people fail more often than the majority -- their trick is to use rejection as a personal learning tool.
This reminded me of something I've heard from a rabbi I know. He's said it on a number of occasions, but I don't know the origin of it. Which is that the difference between a good person and a bad person (for lack of better terms) is that a good person falls down nine times and picks himself up nine times, but a bad person just falls down once.
I think both of these things speak to the same point. The key to success, be it in art or personal growth, or anything else, is perseverance. Screenwriting is a very hard business. There's a lot of competition, it requires a lot of skill, and even when you succeed you rarely get the respect you deserve. The key is to have your own goals, your own means of measuring success, and your own motivations.