Including the fact that she acted as if she didn't recognize herself, it really didn't seem like an act...
Furthermore, she had said, "The boundary between life and death has been blurred, everything will fall into an endless cycle of reincarnation, never ceasing."
At first, Xu Shu didn't quite understand her meaning, mistaking reincarnation to mean people continuously reincarnating through life.
Upon thinking about it carefully now, she meant the so-called "infinite reincarnation," where "one cannot distinguish between reality and illusion, falling into an endless cycle of life, where even death may not offer an escape."
It wasn't about a "long life from birth to death."
Rather, it was about being trapped in a brief period of time.
It involved repeatedly reliving a certain day, or perhaps a few days, or even just a few hours of life.