I think the reason that men are seen as real men if they have lots of sex is because of the typical male/female roles where normally the man has to pursue the woman and win her over in order to bed her down. For some reason, it's deemed "wrong" if a woman takes that role and initiates a sexual encounter or gives in easily. It's not fair one way or the other, but that's probably the basis for it.
Christian apologetics is the art of rolling a dog turd in sugar and selling it as a donut.
