Plot Holes: What Happened to Dianne When She Left the Winchester?

In the film, Dianne leaves the Winchester holding her boyfriend, David's, leg after he was eaten by the zombies. There was a lot of zombies, so we came to a conclusion she was killed right. Wrong! In this segment of the DVD, it was revealed that Dianne actually escaped the swarm of zombies, with not one scratch, and ran and hid up in a tree, where she stayed for a week, and woke up to see the zombies gone. Now, she lives in Birmingham with her aunt.