Im in a horrible situation with my best friend (crush) HELP PLEASE!!?

[Z bReeZie]

So ive recently grown close to a good friend the past couple of months and we tell each other pretty much everything...about how we feel about certain topics, about gossip, about certain things in the past that we regret etc. BUT i have actually been crushing on her for the past year or so, and now that we have became very close friends those feelings have escalated...the main problem though is that she regrets alot of things in the past...certain guys that have just used her for sex, and stuff thats even worse that i just dont want to mention...and just hearing her say these things about those guys and all that other stuff just really bothers me, and i know that she will make the same mistakes with guys in the future because she doesnt hang around the best crowd...but im truly a nice guy and i help her through things like a true friend and its very hard for me to even see her with another guy because i know she will be taken advantage of...and i have come to an agreement with myself that i REALLY like this girl, but i cant tell her because she really needs someone to help her through things that she goes through and i wouldnt want to hurt her by making her feel like she cant trust me...but i only want whats best for her, and she always says im a sweet guy but im not exactly amazing with girls and im not exactly sure why (Im a Junior in high school and have never even kissed a girl) Im pretty sure if i tell her how i feel she would somewhat excommunicate me because Im pretty positive that she doesnt feel the same way...and she recently told me that one of her weaknesses is sex, and she cant stand the fact that she thought those guys actually loved her for who she really was...and i just cant stand that because I KNOW that i would really love her for who she is... i really feel like its my job to protect her, which is also why i cant tell her...it would be detrimental to me if i lost her as a friend, because then she wouldnt have anyone to consult to about anything and that would only hurt her more, which would then eventually hurt me because i only want her to be happy...shes a beautiful person and i cant stand her not being happy with who she is because of her past...im in alot of pain and i really need help... any type of advice would help!!!...We are both juniors in high school!