If a girl says "just friends" then doesn't ever want to hang out... it was just a nice way of rejecting you.
If you were ALREADY friends, and tried something, maybe you've weirded her out a little and shes keeping her distance for now.
Why do you care? Friends isn't what you want, and she'll think you're weak for even pretending that it is, and changing your values to match hers.
I'm still madly in love with my ex and I just this SECOND sent her a long SPAM message that basically said "I still want you. I still want to fuck you. Get in touch if you change your mind" then blocked and deleted her on SPAM lol.
Trust me, do NOT go along with friendship. Don't kid yourself. Anybody on here will tell you the exact same thing.
"Friends only, keep telling yourself it's better than nothing" you ever see that pic? Hilariously spot on.
Call/text this girl and tell her "Look, friends isn't really what I'm looking for. I think you're a great girl and I'd like something more than friendship. Get in touch if you change your mind, cause I'd love to see what we can do." then don't contact her again, ever. Either way you'll get her or somebody better.
I know how hard it is, I'm shaking with regret after what I just did. But trust me, it'll pass eventually. If you go along with friendship, you'll have to listen to her talking about how her boyfriend is too rough when they fuck. You'll have to help her choose sexy underwear to impress him. If he cheats, you'll be the shoulder to cry on thinking "I'd never treat her this bad. Why did she choose him? Maybe now she'll realise and choose me" but it doesn't work like that.
TRUST ME. IT DOES NOT WORK LIKE THAT! Do you really think I'd delete and block a girl I'm still in love with, if friendzone really was the next best thing? Friendzone is fucking painful, man. Don't make that mistake, I beg you. It's something I'll never do again. You'll only get deeper feelings, investing more and more time and effort into her, until you eventually explode and do something stupid like get her on her own and confess your feelings.. only to be rejected again.
I think this is a bit more than you wanted, but yea.
HOWEVER. If you've been in the friendzone for a long time with her, if its a girl you've known a long time, try this out:
http://ipickupwomen.com/easily-escape-the-friend-zone/