I don't have much to add that hasn't already been said. Everybody that has chimed in seems pretty wise. I get those same feelings when I write but luckily I have a very supportive wife that can encourage me without throwing off my expectations. I always think that at least some day my kids might think it's neat.
Also I think if you really do want to get published you should get an agent to sell your book. The CEO of Simon & Schuster mentioned that when she came to my college a few years ago.