Why is sex still a dirty word?

It seems strange that something that people indulge in quite a bit is tagged as tabboo. 
Here again the gender distinction and discrimination comes down with full force,it is quite alright for men to joke and throw around cheap comments and double entrendres but a woman doing the same would be tagged as loose or easy.
A woman reveling in her sexuality as judged but a man is tagged as a stud or a cassanova. 
These terms are back slapping tags that are bestowed upon men as how far they have climbed on the totem pole of sexuality. 
Women are expected to be “pure” and have their hymens intact before getting married lest they give away “milk for free” but men can fool around for boys will be boys.
In this nation of fools,women who enjoy sex even with their husbands are at the losing end-their men think that they are too worldly wise and hence must have a “questionable character”.
This begins the torture at a marital home.
Women and sexuality is a deep subject and a lot can be said on it,not just the aforementioned-which are just stereotypes.
We need to educate our kids and admonish them when and if they ever repeat a sexist joke,comment or even in person.
Parents need to treat each other in a way that would represent no gender doscrimination rather than being in a perfect mother or father mould. 
We need gender benders because i have ways believed that gender is not only what you were born with on your lower torso but also how you are brought up,what influences you. It is all in the mind.
I strive for a day when women and men would be treated at par with one another. 
It is not about being greater,it is about synergy and yin and yang-so to say.