High Rise, Savior

Trapped in the zombie apocalypse, Ivory has set up camp ontop of the roofs of new york, clearing building after another, gathering supplies for her survival.
After the apocalypse started, total anarchy was thrown about, and just as Ivory was to clear her first building, she was almost murdered, and raped.
Years had passed until that, and Ivory and her sniper were sure to survive, until she sees a group of survivors passing, and her trust and gut must figure out where to go from here, stay and fight surely her entire life, or move on to a new one?