True, very attractive people, such as actors and models, have spouses who cheat on them and leave them. Part of that is they know they are partly in a rat race for publicity and getting favors... like hollywood show marriages for publicity or a model marrying a big movie producer... sometimes those are marriages of convenience, that situation can change fast. And I would suspect attractive, rich and powerful people tend to think there will always be lots of green grass fields for them, so they are willing to put someone else first 50-100% of the time. The wiser know you have to be a good person to keep a good person.
I don't think anyone was trained to think attractiveness is of the highest importance, especially people who grew up in the church and with good families. Rather I think most people think physical attraction is not the most important, just an essential element for a mate.
Most people don't select their friends based on physical attractiveness. I think most want their spouse to be their best friend, but they know a spouse is not the same thing as a friend... lots of friends can't be your spouse. Isn't this the essence of the issue?
A Proverb warns about the vanity of beauty as well as the deceitfulness of charm, but not the functionality of physical attractiveness. Proverbs 31:30 ESV: Charm is deceitful, and beauty is vain, but a woman who fears the Lord is to be praised. Proverbs 5:19 ESV: A lovely deer, a graceful doe. Let her breasts fill you at all times with delight; be intoxicated always in her love.