If I go into a grocery store and want to choose a good apple I can pick it up and look at it but I can't take a bite out of it then put it back.
Actually you could. It's possible to take a small bite out of an apple and put it back, off course if your caught then you pay for the apple. Not saying you should do that, but saying you could.
Having sex before marriage is taking a bite out of the apple before committing to it (buying it), leaving it for the next person.
That is a horrible analogy. I've had sex with someone other than my fiancee and she did the same, this was before we started dating and were friends. Human virginity is a cultural idea brought so the man knows the children are his.
If I have sex with someone before marriage, I am likely having sex with someone else's future wife.
If you take this to the extreme then you can also remove: Hand holding, hugs, kissing, looking at, or even thinking about.
I've been there.
As have I. The difference is I don't care who my fiancee slept with before we started doing so however. So long as we both didn't have STDs (and if we did on how to prevent the other from getting them.)
Personally I like it because it means that she knows what she likes and doesn't what she like, thus making it more enjoyable for the both of us.
But if you care so much that the woman remains a virgin till you get married to her, then it's your choice.
Just a little hypocritical though, you've had sex before marriage and she didn't, seems kinda unfair to her.