ASUKA(OFF):“So, while he was waiting in line
for the roller coaster, I left.”
SHINJI:“That doesn't seem too nice.”
UrsusArctos: Shinji sticks to doing something he doesn't think much of for years because nobody told him to stop, while Asuka quickly decides she doesn't like someone for whatever reason and dumps him in no time. Remove the Evangelions from the picture, and their thought processes are so different that I find it hard to imagine them having any reason to be with each other.