shattered reflections (гет)

in one universe, harry james potter became the boy-who-lived, the lone survivor of voldemort's attack on his family.
in another, lily potter was knocked aside by a blasting jinx as a favor to an old friend, too slow to save her son and husband, but fast enough to vanquish the dark lord.
in the last, james survived on account of the last-minute guilt of an old friend, and woke from a potion-induced sleep to find his wife, child, and brother dead, and the world slowly being overtaken by you-know-who.
across space and time, all three potters come across the mirror of erised at the same time, and find that love can pull down many barriers- if one is brave enough to break them.