Study reported on by The Stream:

A new report found nearly half of American millennials don’t want monogamous relationships.

YouGov revealed the research on monogamy and cheating, showing couples under 30 are significantly less monogamous than older generations.

Only 51 percent of people under 30 reported desiring a “completely monogamous” relationship, compared to 58 percent from the 30-44 age bracket, 63 percent from the 45-64 age bracket, and 70 percent from the 65 plus age bracket polled.

[…]Reports also show that men and women are cheating at almost equal rates.

It’s not just adultery that millenials don’t care about any more, it’s premarital sex. An article from the Washington Post found that both men and women no longer desire their romantic partners to be chaste:

Dating has changed hugely over the past generations, and so have cultural ideas about what men and women value most in a mate.

This idea is perfectly illustrated by a chart that economist Max Roser, who created the blog Our World in Data, recently put out on Twitter. The chart is made with data from a study published in the Journal of Family Issues in 2013, in which three researchers compared how heterosexual men and women ranked the importance of 18 traits in wives and husbands, first in 1939, and then again in 2008.

[…]For both men and women, the importance of chastity nose-dived, from #10 in 1939 to #18 in 2008. Emotional stability and maturity, a pleasing disposition, good health, and refinement and neatness also declined for both sexes.

For women, a similar religious background and a desire for home and children became less important in their mates, while men placed less value on ambition and industriousness in their wives.

It goes without saying that adultery is more like to reduce marriage stability. And studies also show that marriage stability is severely impacted by the number of premarital sex partners.  That’s why chastity matters: it’s a predictor of marital stability. If a person can control themselves before marriage when they don’t get any sex, it’s easier to control themselves when that need is being supplied safely and generously. Also, chastity just reinforces the idea that sex is something that is done within a lifelong commitment, not something that is done outside of a commitment for fun and thrills. I don’t that the millenial approach of premarital unchastity and post-marital non-monogamy is going to help them keep their marriages together.

But young people today aren’t interested in looking at studies to figure out how to do marriage right so that it will last. They make their decisions with their feelings. They value what the culture tells them to value, rather than picking a mate who has the skills and abilities to make the marriage last.

How well is picking mates based on emotions rather than demonstrated ability working out? The marriage rates are plummeting:

Gallup poll:

Contrary to what we would expect, given normal demographic patterns of adolescents’ movement into early adulthood and family formation, the data show that significantly more millennials are currently single/never married than was true for those in older generations, and considerably more are in domestic partnerships. Specifically, more than half of all millennials (59%) have never married, and 9% are in domestic partnerships. Gallup has noted a trend toward fewer young adults being married in recent years.

In the 2014 Gallup Daily tracking data, just 27% of millennials were married. According to historical U.S. Census Bureau data, 36% of Generation Xers, 48% of baby boomers and 65% of traditionalists were married when they were the age that millennials are now. For millennials currently aged 18 to 30, just 20% are married, compared with nearly 60% of 18- to 30-year-olds in 1962, according to the U.S. Census. When Gen Xers were the same age, 32% were married; for baby boomers, it was more than 40%.

Millennials are clearly delaying marriage longer than any generation before them, in spite of evidence suggesting that many millennials intend to marry at some point. For example, a 2013 Gallup poll found that 86% of single/never married Americans aged 18 to 34 (roughly equivalent to the millennial generation) wanted to get married someday.

Table:

Who can keep a relationship going when the top criterion is ability to entertain rather than ability to commit self-sacrificially? I hear lots of Christian women say they want to get married “some day”, but there they are in their mid 30s, unemployed, penniless, with empty resumes, backpacking through Europe. The words “some day” sound good to their parents and pastors, but the actions are all about hedonism and thrill-seeking – just what the culture told them to do, in order to have a meaningful life.

Is there a cost to the younger generation turning their backs on traditional marriage, including the norms of chastity, fidelity and permanence?

I saw an article on the Public Discourse that talked about the fiscal costs of abandoning traditional marriage.

It says:

In 1965, liberal Harvard political scientist Daniel Patrick Moynihan was astonished to find that about 25 percent of African-American children were born out of wedlock. Moynihan was deeply worried about this finding because he knew exactly what being born out of wedlock means for a child. Decades of social science confirm what common sense has always taught us: that children born out of wedlock are disadvantaged in every way. They are more likely to be physically and mentally ill, more likely to be poor and unhappy, more likely to have trouble in school and with education generally, more likely to be abused sexually, more likely themselves to abuse others sexually, more likely to abuse alcohol or other drugs, and more likely to engage in criminal activity and to have a disdain for authority.

This, in turn, invariably increases the size and scope of the power of the state. The state must expand to replace fathers who have abandoned their families by providing for single mothers. It must increase its public-health efforts to provide for children whose single parents cannot pay for private healthcare and to treat victims of violence committed by those who have been raised in an environment that has failed to equip them for a robust and peaceful social life. It must create and maintain adoption agencies to care for children whose parents are unfit or absent. It must commit more funds to police departments to address crime that results from families breaking apart (or failing to form in the first place), and hence failing to instill virtue in children. It must commit funds to the creation of prisons where criminals are to be kept. The list goes on and on.

The economic costs of abandoning social conservatism, then, run quite high—in addition to all of the unquantifiable social costs of broken families, deaths, broken relationships, and ruined lives. It is no surprise that leftists, committed to consolidating power in the state, have sought to undermine the family: they realize—better than many fiscal conservatives do—that a flourishing marriage culture is required for free markets and limited governments to exist.

So, there really is a cost to the embrace of moral relativism. When morality goes, expensive things happen, and government grows to pick up the costs. The bigger the government grows, the taxes are required to pay for it, leaving you with less of your own money – less of your own freedom to live how you want to live.