* SPOILERS* (?)
I've always thought Aerith loved Cloud because she saw Zack in him, and that's hinted at if you get her as your Gold Saucer date. She also said something like "I hope you find yourself someday" or something. (It's been a few months...), so I think she kinda got over that when she knew what she had to do (trying to stop Sephiroth and all.) So I think she knew about how Cloud was, how he had Zack's memories, assuming his identity and all, she saw him in Cloud.
Okay, did that make any sense?
But yeah, I hope you know what i mean.
Actually, Aerith didn't really bug me that much. (Barret did though...). She was kinda cruel towards Tifa, but only during the absolute beginning of the game. (Up until you rescure Tifa from Corneo.) After that , she seemed nice to me. Meh.