Gorrath tried to kill Ally at a rock concert, which would directly erase Kiva from history, preventing MEGAS from being sent to the present and potentially ensuring Glorft victory. Due to Coop and Co's intervention, Glorft plan failed.
Ally later decided to return to Brooklyn, believing that all the mess with aliens and time travel is too much for her.
Ally appears to be quite skeptical about everything happening around her, even as she witnesses its reality firsthand. She even rejected Kiva's request to at least know each other better, despite them being (technically) family (Kiva being her descendant). She seems to be as dismissive as most of Jersey population, and remains emotionally unmoved even when Glorft threaten to kill her, pushing away any and all who try to help her.
Much to Kiva's displeasure, Ally has shown a mutual attraction to Jamie, even going as far as stopping to help him at the moment of danger.