I agree with
@IronVader501 on all accounts. Not only is she having to re-experience the trauma of dying and/or being murdered (in very painful and grotesque ways), but she retains her memories and consciousness every time and that is horrifying. Her reaction (although extreme to the characters who don't understand what's happening) is justified and we can empathize with her actions.
Edit: Plus, she bears the burden of having to move the plot forward. She is literally being forced to find solutions (even to extreme points, but the genre's changed so it's okay) in order to survive and save Jeha.
From the synopsis, it says that she's going to have to work with the "extras" to solve what's going on and follow the plot. If I recall correctly, I think at the beginning, she said that when she first entered the book she was able to see people but once she went on about her everyday life they all became the same to her to the extent where she couldn't distinguish them. It's my hope that as she works together with the rest of the students, that she's able to see the other students clearly again <3