Wives seek individual expression yet husbands want a routine home life.
Both men and women - well beyond childbearing years - want to couple, but not all of them yearn to wear a wedding ring.
And society doesn't seem to care. The first generation to celebrate seemingly ageless vitality and longevity is making up its love lifestyle as it ages, says Abigail Trafford.
The Washington Post columnist is the author of the new book, "As Time Goes By: Boomerang Marriages, Serial Spouses, Throwback Couples, and Other Romantic Adventures in an Age of Longevity."
This serious study of the new couplings after 50, 60 and beyond attempts to define the indefinable. The surprising conclusion - that sex is more fun after 60 - came after Trafford spent more than a year studying relationships and interviewing hundreds of couples.
Yes, she brings her own experiences to the party. Trafford's been a chronicler of aging for many years. She's been divorced twice, is now single and has what she defines as "friendships." She also defines herself as the "gaga grandmother of three." Grandchildren, she says, are the triumph of love.
But we should maybe define "love," right? What's "love" at 30 got to do with "love" at 60? The answer is a lot and a little.
First, toss out all those stereotypes of past "old" love. The age of longevity brings its own discoveries.
In marriage, for example, longevity often means the paradox of finding new fulfillment within a relationship. The challenge is to fall in love again,
Trafford says. And marriages can count on two years of conflict when someone retires - particularly if the man retires first and the wife continues to work, maybe even soar in her career.
As for the singles? Well! The good times are rolling.
"Society has really changed and is encouraging people who are single at this age to form relationships, maybe marry, certainly recouple. It's like super going steady," she says. "There's a new attitude: I played by the rules. I was faithful and raised children and now I'm single and what have I got to lose?"
Women are loosening up and men are loving it, she says. Want proof? Read her interviews on triangle marriages.
Yes, there is more to falling in love than falling in lust, Trafford says.
While the new definition of marriage expands relationships beyond the legal framework, "married or single is not a big issue of identity," she says.
"And I think that's pretty exciting. It's the culmination of all those old social forces - having no rules and getting to make them up. Of course, mistakes will be made, but the model I try to give people is to open your heart and love. Sure, it's risky and you can be hurt, but in the end, you triumph. Don't be afraid to love."
Trafford has her own definition of the "Renaissance couple." They have admiration and respect for each other. They influence each other. No one person hogs center stage. They have more confidence in themselves and this helps them to stay together.
Sure, these independent wives got their backbone, in most instances, because of the Women's Movement and the acceptance of women working outside the home. Perhaps this 21st century approach to coupling after 50 reflects yet another chapter in this grand experiment.
But maybe, just maybe, men and women are learning there is more to love than marriage and coupling.
There is a network of love, Trafford says. She's talking about the people you can't imagine living your life without - friends, family, lovers.
"You need about 10 of these people," she says. "If you get to three or below in your life, you will have health and isolation problems. It's really important to have a sense of the team."
A team of lovers. I like that. They make your heart happy. Don't forget them on Valentine's Day.