Wait, I didn't read your entire story, but you listed your girlfriend/fiancee as your spouse on the application when in fact you were just planning to tie the knot with her?
For your sake I hope I misunderstood.
Yip, that's what he said. I'm sorry to tell you, as E59th has hinted, if you do win you will be disqualified at interview level. If you listed her as your wife but your marriage certificate is dated after the DV closing date, they will know that you lied on your application form. It would have been correct to enter individually and list yourselves as single. If you win and get married, you can prove that at the interview and try to have her added to your Green Card. Either way, you will not make it this year. Sorry to be the bearer of bad news, but hopefully you will fill in the form correclty next time.
Good luck to everyone, I too am waiting with bated breath for the NL's to arrive.