What could win her over?

You sound like a real sweetheart !! Just keep on being as nice as you are and I'm sure she'll soon realise that you could have more than a friendship. You could try spending more time together doing 'couple' stuff, which might give you the opportunity to say something like ' look at us - I bet people think we're together !!' You'll be able to tell by her reaction whether or not she sees you as a friend or boyfriend. Good luck x