See your flawed logic?
It is human to err, and humans ERR when they engage in pre-marital sex, infidelity and prostitution.
And a further case in point, many people respect the sanctity of marriage and DO NOT err with regards to the above.
I disagree with any attempt to "normalise" the behaviours described above. I accept that all people often have moments of weakness and can succumb to wrongful behaviour, but I do not accept that the wrongful behaviour then somehow becomes "normal" or right.