Doesn't the dialogue during the Aerith date in Gold Saucer, should you get her, shows she really only cares for Zack?
no in fact she says she wants to get to know the REAL Cloud because she perceives he's not himself. If anything this proves she was over Zack and ready to move onto Cloud.

And isn't it obvious from AC Aeris is busy having ghost sex with Zack?
uh... no