Don't listen to them this friendzone talk is bullshit. I friendzone girls all the time, i.e. I tell them everything and treat them like the closest of my friends. Doesn't stop them from eventually climbing all over my dick. In fact, pretty much every last girl I've befriended have somehow ended up wanting a piece of me, I don't even push it.
Just be yourself completely and don't try to be something you're not to appeal to her. Thats why these guys get stuffed in the aquintance but no further-pocket, they have these ideas about what they think girls want them to be and act like that instead of being frank. That deprives them of every interesting aspect they might have had.