Few days ago I was reflecting with my wife about sex taboos in Chinese culture and broadly about sex taboos in any culture. On my point of view sex is something important but not too much important, I mean that it is just one among the many things which are important in a couple relationship. I think there are two ways of giving it too much importance, I mean more importance than it actually has: idolizing it or making it a taboo.
In the past there were not condoms, so there were a kind of reason for inculcating in the mind of young girls any kind of fear about sex… fortunately now a very simple technology changed the objective situation and there is no more need to fear to remain pregnant and also many illnesses can be avoided in this way.
However the cultural heritage seems to still influence many people. I think this is because the cultural taboos about sex were born in order to solve the objective problem of unwanted pregnancy, but they have always appealed to and tried to manipulate subjective emotions, so even if nowadays the objective problem has been solved, the subjectively implanted control structures are still there.
Lastly, note that in general in a archaic society older family members are used to fabricate myths and taboos in order to indirectly control (many things and among them also) sexual selection, so it seems to me that this is also a matter of power__the power of choosing your sexual partner by your own.
The discussion is open, but no one has taken the first step yet... Oh! For heaven's sake, start saying something Janet!