Sorry this isn't what you want to hear, but if you've been talking to her for weeks and haven't already made your romantic intentions clear, you're in a bad spot. Being straightforward and asking her out in a romantic (honest) way takes courage, and women are attracted to confident men who ask for what they want. Pretending to be her "friend" when you have these feelings for her is dishonest and it will get you nowhere. Tell her how you feel and if she doesn't reciprocate, then forget about her and move on to the next one.