Dating my best friend, but there's no intimacy

[18&Life]

So I've been really close friends with this girl for six years now, and we started dating about three months ago. Everything started out good, but now it's falling apart. There's just no physical side to the relationship. She's been through some tough times with rape & past boyfriends so I have this huge fear of doing anything-especially since she shows no signs of wanting anything like that. I know she does though, because we've kinda talked about it & last weekend for valentines day she bought condoms just in case(I found this out from her mom). It really doesn't help that the other relationships we've had the other person always took the lead so neither can really start anything...and I don't want to lose her. I'm 18 and have been with other girls but am still a virgin-I'm the kinda guy that while I wouldn't have married any of them, there has to be some feelings for me to be into it. I really need help here...I've never been as lost as I am now & I don't want to lose the girl I've been dreaming of being with for years.

Please help me