It is time that you concentrate on finding another woman to complete you. Lingering and longing for something that is out of reach will cripple your psyche for years. It would be convenient for you if she would list every single thing that explains why she only wants to only be friends and not lovers. But then you'd probably change yourself for the worse just to please her. This was probably not meant to be. Hanging around will only make things worse. The friendship can be saved, but only if you can accept the terms. Can you? Will you?
Finding these mythical creatures we call SoulMates is tricky because there are dopplegangers running amuck. These 'gangers disguise themselves as our One and Only, doing what we want, looking the way we like or saything the things we like to hear. But there is something about them, or something about us, that makes it impossible for a romantic union to develop. That is when you know you have encountered a doppleganger. We can all hang around to see if their minds can change and accept this supposed fate that we should be together, but before you know it, you're older and you've missed some of life's blessings because you're chasing after something that cannot be caught.
Find someone else, for your sake and for the friend's sake.