Rejection is rough. When I was working as an editor I solicited a submission from a writer I greatly admire and envy. And in the end the other two editors passed on what she decided to send us for the journal's consideration. It can be a very rough process, submitting and pitching, and its even worse when publishers show interest and pull the rug out from under you at thr last minute.
Still, sometimes it takes more luck than most people realize, and that it got so far with Cartoon Hangover, even as correspondence, is super impressive. I'm excited to see what comes of this in the near future!