Two things - she may just be one of those individuals who come to their full sexuality later in life. Or she may have been traumatized by someone in the past. Take her out to eat at one of her favorite eating places and ask her what's going on in her life.
If she is studious and academic why don't you give her the book and let her read it when she's ready. If she's not ready she's not going to make herself read it? It will be there when she is ready
Regarding boys; they are idiots! Lol. She might be a lesbian and she might not - I would be thankful she's not chasing boys abandoning school and having sex!
I'd guess she is totally normal. Buy her some of the good books about sex written for kids her age recommended on Amazon, tell her you're there to talk to her about anything in them that she can't believe or understand (or anything that has happened to her), and give her some space. It's also possible she is not interested in boys because she prefers girls, I hope this would not shock you if so. (Many lesbians and gays know from a surprisingly early age, or know they feel "different" when their peers giggle about the opposite sex but just don't know why.) If that last possibility turns out to be the case, please don't worry that this is not "normal." (Though it isn't what we think of when we become mommies, that someday our kid's partner might be someone of the same sex, that's true.) Try to relax and stay open, and grounded in your love for your daughter, no matter if she simply hasn't hit an interest in romance or sex yet, or if she has but is just not interested in talking with you about sex, or if she is not talking to you because she thinks this is something you wouldn't be ready for. Good luck, mama, your kid is fine.