Preface: I went through a religious phase in my teens. When I was 19, my first real boyfriend would get hard-ons through his jeans (poor thing, I think back now!!) and they scared me... I didn't really know what was going on, so I basically ignored them. We were together for a year and our pants never came off, once. It was only kissing and a little bit of boob-touching, but I wasn't even comfortable with that, after a while... I ratched back my boundaries pretty severely because I was so afraid of breaking the evangelical rules we were supposed to be living by. (I'm a pretty black and white person, I learned... I either follow the rules to the hilt, or I break 'em all.)
I did not really allow myself to become interested in sex and masturbation until I was 22 years old. I didn't encounter, let alone touch, an actual penis until I was 24. By that point, I was MORE than ready/eager to explore and get to know this new member in my life.
Are you willing to wait 8 more years?
(I don't think it will take her that long, but seriously, you never know what is going on in their heads... for me, it was religion, but it could just as well have been something else.)