how did stupid unethical dating culture start, where people have sex like dogs. Throughout history people are just married to one person.?

It started with atheists

What little part of history did you isolate to form this opinion? People have been poly-amorous since the start of time. Monogamy is a new and not very successful experiment.

Darn those youngsters and their healthy libidos!

I'm sure you love living in your fantasy world.
Me?
I love reality.

Polygamy is the traditional form of marriage that Christians changed before they started whining about people trying to change the traditional form of marriage…
~

Throughout history?

Wow. You must have been reading a highly selective and severely edited history of humanity.

The sixties hippies with sex drugs and rock and roll was the beginning.

Well, it makes sense if you like sex and want to make sure your partner is compatible.

Looks are definitely deceiving in that regard.
I didn’t have sex with my high school sweetheart until after I had a deep emotional connection to her. Then I found out she was frigid.

Though out history until the 1900s women were more or less property of the men.

I think you need to read more history.

Contraceptive pill and feminism circa late 1960's.