Close-up of hands holding. (iStock)

We began meeting every week in 1998, eight women, mostly in our 30s, some married, some single, most of us enjoying professional success and the energy of relative youth. Ostensibly, we were a Bible study. But as we inched toward midlife, the time we spent talking about our lives — about bosses and unemployment, the death of parents, the slow-motion agony of being single year after year, and the razor-sharp hurts of marriage — gradually, those stories nosed out theology.

Our group was a little like Walmart: one-stop shopping for career advice, logistical help and emotional support. Then, three years ago, we became, for a few weeks, a proxy family. Beth, who was in her late 40s and single, put her name into the foster care system. (I promised my friends confidentiality and changed some names.) Within days, Beth received a call. She had 48 hours to prepare for a radically different life with her new charge: a heroin-addicted baby born several weeks prematurely. The hospital sent her home with one diaper.

That night, Samantha made an emergency run to Target. “I remember calling Beth, saying, ‘Okay, I’m in the baby section, tell me what you need,’ ” Samantha recalled. “… I was just walking up and down the aisles, telling her whatever I was seeing, saying, ‘Do you need this? Do you need this? Tell me what you need.’ ”

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Over the next few days, our group mobilized, a tiny army transporting critical supplies to the front line: a changing table, toys, play mats, clothes. Jody, a network television producer, decorated Sophia’s room. Jody’s husband, an accomplished photographer, took professional photos of the baby. For the first few weeks, Beth could not take Sophia out of the house. She was too fragile. So we delivered lunch, or dinner, or groceries.

“Everyone was calling and emailing. It was an overwhelming experience,” Beth said. “I don’t have family here. You all were my family.”

If the details of this story are unique, the context is not. If you are middle-aged, there is a fairly good chance you are alone. As people have left their home towns to pursue their careers, as record numbers of baby boomers have joined what researchers call the “Gray Divorce Revolution,” more than a third of adults between ages 45 and 65 are fending for themselves. For them – for everyone, really — friends are no longer a luxury. They are a lifeline.

This is more than a psychological phenomenon, says James Coan, a psychology professor at the University of Virginia, who directs the Virginia Affective Neuroscience Laboratory. Friends share the burden of life, helping you deal with 21st-century “threats” — office politics, the no-show of the babysitter, the health scares or spats with your spouse, the growing needs of your aging parents. We are wired to rely on friends, and this trickles down to our biology.

“When you have more friends, you don’t have to use as many of your own personal resources to deal with the world, so you can use those resources to build yourself up,” Coan says. “You’ll grow hair, you’ll repair skin, you’ll beef up your immune system. So you’re more prepared to deal with what life can hurl at you.”

Indeed, studies show that people with a network of friends live years longer than those who are alone. They recover more quickly from cancer. They are less likely to suffer a heart attack or stroke. They ward off depression, and are far more likely to keep their memories intact as they age. Many of these studies suggest that friends matter more to your health than family. After all, you can choose the friends who bring you joy and assistance, and can drop the ones who drain you. You generally do not have the same latitude with family members.

And yet, just as we need them most – at midlife, when things get really complicated – we tend to drop them. Midlife exerts a centrifugal pull. The forces that fling you away from your friends spin faster and faster until they can stretch and ultimately snap the bands of friendship. I watched this happen to my group: Over the years, children vacuumed up our time, our job commitments and travel intensified, parents got sick, needed tending, and died. Meeting every week became a burden. We remained friends individually, but the group dissolved.

When I described this collapse to Robin Dunbar, an evolutionary psychologist at Oxford University, he nodded, unsurprised. His research has found that human beings can only maintain five close relationships at one time, because such relationships require investment. If you don’t invest time in a friend, she drops down to a less intimate level, creating further disinvestment – and distance. And romance! Romance throws your close network into a state of chaos. Your new love shoos some friends out of the henhouse so he or she can create a nice, big, comfortable space in your life. The beloved takes up so much of your time and emotional space that he or she colonizes two spots in your inner circle of five.

What happens when you have children? I asked Dunbar.

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“I think you lose almost all of your friends,” Dunbar said, laughing, “because you just don’t have any time at all when they’re young.”

From a mental and physical health standpoint, dropping friends is precisely the wrong move – and yet, it is one that more middle-agers are taking. Indeed, the AARP has found that the loneliest people in America are those between the ages of 45 and 65. This invites catastrophe, because loneliness is lethal. Meta-analyses have shown that feeling isolated and lonely is as bad for your health as smoking 15 cigarettes a day. Loneliness predicts cognitive decline more than does depression. Scientists believe that loneliness lowers your IQ over the course of your life, and that it makes cancer replicate more quickly. It robs you of sleep. And if you are over 60, loneliness makes you far, far more likely to die.

“It’s a significant health problem,” says John Cacioppo, who studies the health effects of loneliness at the University of Chicago. “Not to mention it makes your life miserable.  That would be sufficient reason to want to do something about it.”

What to do, given the terrifying consequences of loneliness? This was the question that haunted me as I surveyed the blank space in my calendar that my friends used to occupy each week. The problem – and isolation – grew more acute after I left my job at National Public Radio for the quiet and isolated work of writing books. I settled on a plan. Look two directions for friends: back in time and around in my world.

Looking back, I have tried to burnish my old friendships, including ones from childhood. In this, I am taking a page from a woman I interviewed who was dying of cancer: In the end, she wanted to spend time with her family and her friends from elementary school, who had known her in her purest form. I am also looking around, gathering friends among fellow authors, my church, and in my new-found hobby, cycling, which seems to draw a disproportionate number of vibrant and fiercely competitive 50-something women.

As for my group: Beth has adopted Sophia. We meet on occasion, for Easter, for Christmas, perhaps in the hope that one day a decade or two hence we’ll find our way back. It could happen; we have shared a lot of history and wine. But never far from my mind is the fact that science emphatically confirms the wisdom of the Beatles. We get by with a little help from our friends.

Barbara Bradley Hagerty is the author of  “Life Reimagined: The Science, Art, and Opportunity of Midlife”.  You can follow her on Twitter @BBradleyHagerty

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