Taylor, Cara, Jackie, and Veeves only show angst briefly in reaction to knowing that everyone and everything they knew outside has long been gone, given that it has been over ten millenia outside since they first entered the cave. Justified in that they were focused on not getting killed by hostile cavemen. At the end of the movie, when they rescue Furby, Hopper, Hopper's parents and Hoppers' sister, they show little angst as they had years to come to terms with and adjust to life over ten thousand years after their own time.
There was one brief moment of this, as one of the girls mentions that she has a date on Saturday. Of course, by that point that Saturday had been several thousand years in the past. There is also a brief "everyone we know is dead" moment, but this passes quickly.
