Hi iron2fe, it is really good that you sound like you care about her so much and are trying to be so supportive, but before this: "I want to figure out what I can do to help her start to acknowledge the fact that she is a sexual being and that it is okay to feel urges or attraction to people in a way that is less than innocent" it might help to talk to her and find out if there's a WHY.
Any negative experiences.........(??) , any fears. any anxieties............?
From what you say there's a chance that she's may not just come out and say.........but if you could at least let her know that if there is anything, it's OK to talk to you about it, you'll listen, be there for her and help her if you can......and maybe at some point she'll feel more comfortable in talking.
That I would say was vital.....but......if that is just "part of who she is"........she doesn't want to talk about it.........she feels comfortable with it/with who she is then why not let her be who she is and support her with that. I'm sure there are going to be/can be many other aspects of your friendship (and she can still be a valued friend) without as much talk about relationships. Or maybe find with her certain levels/types of conversation about relationships that she is comfortable with if that topic just arises naturally.

Now this is just a maybe, and maybe well off target bear that in mind!! but........:
As for some parts of what you're saying maybe (if there's nothing she needs help with!!) she's more embarrassed/sensitive/private in having those things come up with yourself or with someone she doesn't have that sort of intimacy with. But given time and the "right" person/relationship she might feel more comfortable/relaxed around those sorts of things. And nothing has to be wrong with that.

But back to......try to talk to her about it........say how much she means to you.....say that you're just concerned about her because........say that you'd like to be able to be there for her if there's anything she can tell you about/or wants to talk about........you get the picture, right??

And again, it is really good that she has a friend who seems to care about her as much as you do.

Alison