New, old, stale. Entrepreneurs get to have many tag-names added to their title. I believe that entrepreneurs are the people who build something of value, perhaps something that anyone could have built before, but didn't because the time wasn't right. Are entrepreneurs known for their perfect timing?
Don't give up; not just on what you truly want, but also the seemingly useless and boring things that you have to do "just to get by." Everything has potential, every single opportunity is a piece of your puzzle. It's just a matter of figuring out where it fits -- and revealing the picture it creates.
Too often we focus so much on a door that has closed abruptly and unexpectedly in our faces that we don't realize that the world is full of other doors that are open to us. You won't find your happiness demanding that a certain closed and locked door reopen; all you will do is miss seeing alternate avenues of opportunities that are available to you.