15 year old girl won't leave me alone *sigh*

So I haven't posted in a while but something has really been bugging me lately.
A friend of mine has recently been questioning herself and is uncertain whether she is bi, lesbian etc or is just confused. She comes to me a lot for advice because I remember going through a lot of the same stuff when I was her age (she is 15 and will soon be 16 and I have just turned 18) and remembering what a sensitive time that was (I'm also a friend as well). I obviously have no problem with talking to her about things and giving the best advice I can but recently she has been extremely close to me. Like for instance she texts me constantly (basically all the time) and when we are in person she quite...forward/flirty I guess :S.
I'm really hoping that I am reading the signs wrong and that she is just messing around for banters sake or just needs some friendly advice about what she may be going through but I can't help but think that she is trying to come on to me. I really don't want her to do that because 1. shes a minor and I'm a senior so it wouldn't work anyway (shes been going out with people over the age of 18 because she LOOKS a lot older than she actually is) 2. I like older women and so she is certainly not my type (I'm not into younger girls/women) 3. I am also cautious that she might be confused so I don't want there to be any complications (I don't wanna say she is 'just confused' because that can come across as patronizing but it could be a possibility if she is unsure of herself).
What should I do and say? I want to try and find the right words not to insult or patronize her or give her the wrong impression. Hopefully my theories are wrong but I can't be sure. Advice would be greatly appreciated (*hug*)

 

Thanks for replying I certainly don't have any feelings for her in a 'romantic' way because she is not my type (also she is younger as well). But the main concern is what she might do if she goes off with older people, like flyinhernikes pointed out, a 15 year old dating people over 18 (bare in mind she is still a minor) can lead to a lot of implications and possible danger/trouble. Its not my place to pry or get into her business but I (and a lot other people) can't help but be a little concerned about her. She has a tendency to get in quite a few pickles and situations that can be quite dangerous :L
Anyway thank you again for replying