How does a culture rooted in the discipline of Christianity devolve into one that embraces relativism and the autonomy of the individual? Slowing and patiently. In America, it has taken a multi-pronged campaign of capturing the educational system along with the major media outlets that portray nice people who embrace worthy causes, and who incidentally happen to be adulterers and fornicators. Helping the poor and oppressed trumps being faithful in marriage or waiting until marriage for intimacy. Slandering is acceptable as long as the person or group you slander is depicted with politically incorrect views. The audience is given the subtle (or sometimes not so subtle) idea that some transgressions of God’s law are worse than others.
I recently watched a film where an adult daughter railed against her father for his repeated infidelity towards her mother. Despite the fact that the daughter was involved in a sexual relationship outside of marriage, she felt righteous in her anger toward her dad. His defense was that all those women meant nothing to him; his affection always remained for his wife. It is noteworthy that both father and daughter were portrayed as upstanding attorneys who refused to compromise with the law or their integrity.