Hi Bro,
the people before are telling you what you know already and not offering solution. What has happened here. You have put yourself in the friend zone. I am a trained pick up artist and you need to change it very slowly to get her to become interested in you sexually and for relationship.
Can I suggest you go to www.puatraining.com, www.friendtogirlfriend.com www.attractionexplained.com
What every you do NOT confess your love in a sexual way with her until you build attraction. She will run otherwise. You need to break rapport with her, tease her, show her that you are a sexual being, talk about other girls, don't have to much time for her, use sexual themes in a light hearted matter. Basically you are a guy and want to bang a girl you like...thats normal.
checkout the blog.
http://www.puatraining.com/puablog/page/4
Look down Friends to Girlfriends ..... (use google & Youtube to help you get advice) In the pick up community in US. Adam Lyons, Hypnotica, Sinn, Richard Gambler are famous people. Get some programs and change your situation.
Use this in a search term....to help you further with women www.puasummit.com
Get into this and you be able to have more women than you need.
Wish you best Vincenzo