Never Say Die — Kimberly Gould

Cassandra has survived the zombie apocalypse. She and others have banded together to search for more survivors. On one such rescue mission, the zombies get lucky and Cassandra is their victim. Instead of dying, Cassandra finds herself in her own past, days before the outbreak of the virus that turned all the adults to mindless monsters. She has one chance to stop it all. Well, maybe more than one.