Honestly, friend, she's keeping you around for a handy "what if" source if anything ever goes wrong.
You're in friend zone. Perhaps she genuinely does have moments where she thinks you might be right, but as of five years that has never happened.
You are an eternal second or third choice and whether she consciously or subconsciously does it is irrelevent. Get over her. If it hasn't happened by now, in every likelihood it never will. Cool off her for a few months, start looking around your college, hang out with some other girls, and only reconnect when you are done with ever desiring her.
She may be a good friend, but she's wrecking your love life, and if she was a good friend I'd hope she'd have realised that by now.