It drives me *nuts* that people think that Ginny is pining after Tom Riddle. She wasn't a big presence in books 3 and 4, but as she was still tongue-tied, it's safe to assume she maintained her crush on Harry until she got smart about it. It doesn't seem likely she'd do that and still be "in love" with an admittedly handsome 17 year old ghost - although there's no evidence she saw him until she opened the Chamber, and then he was trying to kill her.
He also possessed her and made her do awful things.