A young friend whom I've adored since she was a toddler approached me last weekend, lifted her hand and, with a delighted grin, flashed a stunning engagement ring.

I actually screeched with joy before pulling her onto my lap, something she graciously allowed me to do.

She'll be 30 when she marries, which makes her unusual — but not for the reason you might think.

What's unusual is that she's getting married at all.

Study after study is confirming what a growing number of baby boomer parents already know. Many millennials (generally considered those born after 1980) are dramatically delaying — or rejecting outright — that walk down the aisle.

They have their reasons.

As they adjust to long-term singledom or cohabitation, their parents must adjust, too, with nary a road map to answer burning questions:

Will they be happy?

How will they manage financially?

Will we ever have grandchildren?

Mostly that last one.

"How do we parent them?" asked Stephanie Coontz, professor of history and family studies at Evergreen State College in Olympia, Wash., and director of research at the Council on Contemporary Families.

"With the old way," she mused, "you stopped parenting them and they presented you with a grandkid you could re-parent. We never had to renegotiate the relationship. Now we have to start learning to like them as people."

Coontz, the mother and stepmother of two young adult sons, admits to "a certain amount of unfulfilled grandparent hunger." But she assures fellow parents that they shouldn't panic. The new reality also presents opportunities for uniquely rich relationships with those headstrong emerging adults.

First, though, the numbers.

Pew research from 2014 revealed "historic highs" for America's singles. Approximately 20 percent of Americans older than 25 reported never being married, compared with 9 percent who said the same thing in 1960.

In May, the forecasting firm Demographic Intelligence projected that the marriage rate will fall to historic lows by 2016, with long-term ramifications.

When today's young adults reach their mid-40s to 50s, up to one-fourth are likely to still have never been married, noted Pew authors Wendy Wang and Kim Parker.

"This is not to say that [they] will never marry, but our analysis suggests that the chance of getting married for the first time after age 54 is relatively small," Parker wrote.

Why are they just saying no to the bridal party bus?

Many singles aren't ready to settle down. Others want to be more financially stable, or they're waiting for their mate to become more financially grounded.

Many say they haven't found the right person.

Margaret McCray, executive director of the Westminster Counseling Center in Minneapolis, noted another reality. If they've lived through their parents' divorce, as many have, "there's the devastation of that, emotionally and financially. Living together feels a whole lot easier and less risky."

Plus, there's little stigma anymore to being single, or living together, or even having a baby outside of marriage — the experience of 41 percent of women today.

'A lot more closeness'

But McCray and Coontz also see reasons for optimism in young people's preference for going it alone.

McCray recalls feeling concerned as she guided young couples through the church's premarital Prepare/Enrich program.

"In a discussion about the realities of marriage, younger couples would say things along the lines of, 'I want our marriage to feel this romantic for the rest of my life or I don't think I want to get married.' I was just floored at the naiveté," McCray said. "Putting off marriage until you're older and wiser might be a good thing to do."

What's important in the interim, she suggested, is to have a strong social network of friends and family members you can count on.

It's also important for parents not to project their own angst on the one-fourth who may never tie the knot.

They're often very happy, thanks.

"Never-married singles, especially women, have very happy lives," Coontz said. "In their 40s and 50s, it's, 'Oh, my goodness, regretful.' But by their 60s, they're almost as happy as married people and more happy than divorced people."

One of the most surprising trends is the growing number of singles entering their first marriages way past the 50-year mark.

"I have seen, in my own circles, women getting married at 55, 60, one at 67, every single one for the first time," McCray said. This was after many years of cohabitating for a few of them.

Married or not, McCray and Coontz agree that boomer parents have a unique chance to develop fulfilling friendships with their millennials.

Coontz recently traveled to Thailand with her 33-year-old son and his girlfriend. "Wallow in that!" she jokes.

"We're finding that there's a lot more closeness," she said. "The millennials are much more likely to say, as an adult, 'I can talk to my parents. I actually appreciate hearing their views and they appreciate mine.' "

McCray agrees. "Maybe you can't go from being parent to grandparent, but you can go from parent to real friend."

And, about those grandkids?

If you can't wait, there are lots of ways to get your fix elsewhere, they say. Adopt a young neighbor for a few hours of baking. Read to children at a day-care center or school.

"So many kids would just love it," McCray said.

Coontz has struck up a friendship with the children of a neighborhood family, inviting them over to play.

The biggest bonus, she said with a laugh: "It really takes the pressure off your kids."

gail.rosenblum@startribune.com

612-673-7350 • Twitter: @grosenblum