Dawn leaves the classic "just friends" voice mail. Some real zingers. "You're an amazing guy..." "Why mess with a good thing?" "It's not you, it's me..." and, of course, the almost clichéd, "This has nothing to do with your missing arm..."
All of this would be cruel enough, but she leaves it on Jim's voice mail. I guess this is how the story ends because one thing I can absolutely guarantee: Jim is as gone as his left arm. We will never hear from that guy again.