The most accurate difference between the challenges that Alyssa and Juliet face, based on the provided passage, is:
Alyssa has to decide who she wants to be with, Reid or Austin, while Juliet does not face a similar decision.
This highlights the fact that Alyssa is navigating her feelings between two different characters in the context of her interactions, while Juliet in "Romeo and Juliet" faces a more fatalistic circumstance regarding her love for Romeo and the consequences of their families' feud.