Do you have a Valentine's Day hangover? Have you read a million articles and heard a million news reports about marriage and love and crazy proposal schemes and so on over the last days and weeks? Couples and romance are big news — and big business. With so much recent emphasis on the couple bond, romance, love, sex, and so on during the build-up to Valentine's Day, some other very important relationships may not have gotten their due.

I'm talking about you and your friends. Why you need them, what they do for you, why you literally can't live (or can't live as well) without them.

I am honored to find myself a finalist for a "Books for a Better Life" award along with Jeffrey Zazlow. You know him — he co-authored The Final Lecture with Randy Pausch, and more recently wrote The Girls from Ames, a chronicle of the lives and friendships of 11 women from Ames, Iowa over the course of 40 years.

Zazlow found that, in spite of the fact that the women moved apart and lived in eight different states, their friendships sustained them in critical and remarkable ways. One woman lost a child to leukemia. Another battled breast cancer. The women dealt with transitions like divorce, job loss and the stresses of caring for their kids and their parents. Over and over, they supported one another with phone calls, gifts, and emails, extending and benefiting from the tangible and intangible rewards of friendship.

What does science have to say about social support and emotional and physical well-being? You might be surprised. Last spring a New York Times article summarized some pretty incredible research about what friendship can do for us, concluding that friendship is a, if not the, key ingredient in the brew of a healthy life.

A 2004 Ohio State University study looked at the effects of the stress hormone cortisol on lone hamsters versus those paired with a furry friend. Researchers found that skin wounds healed nearly twice as fast in the befriended hamsters. These animals also produced less of the stress hormone cortisol than did unpaired hamsters. Here's something else: if the researchers deliberately stressed the hamsters by putting them in a confined area, those hamsters who had company in the stressful situation produced less cortisol than the ones confined alone. And the presence of another hamster increased the hamsters' oxytocin levels. That's a feel-good, happy type hormone that is also produced when you nurse a baby or fall madly in love. The study's lead author concludes, "Stress delays wound healing in humans and other animals, and social contact helps counteract this delay." That's right, friendship helps us heal.

Another study of 3,000 nurses with breast cancer found that those without friends were four times as likely to die as those with ten or more friends. And here's something amazing: the women didn't have to see or even be in touch with those friends for the friendship to have a protective effect. And just last year Harvard University researchers found that a good network of friends could promote brain health and improve memory function as we age.

Social support is good for guys, too. A Swedish study found that only smoking was a greater predictor of having a hard attack than was not having friends. That's right, not having friends can be almost as bad for your health as smoking. As for smoking alone — okay, I'll stop!

When it comes to your mental health, it seems friendships give us a leg up and a positive attitude, a sense that we Can Do (what woman partnered with someone with kids couldn't use that?) One of my favorite studies on the topic is the slope slant study. College students were asked to stand at the bottom of a slope and describe its steepness. Those who stood with friends rated the slope as less steep, and the longer they'd been friends with the person they stood with, the less steep they rated it. Climb every mountain — with your best pal.

What does all this mean for women with stepchildren? I don't think I need to spell it out for you. In a stressful situation your best bet may well be to find some supportive friends, and then hang on like hell. Get out — a good goal might be once a week — away from your home, your partner, and his or her kids if they're in residence, and have a good time. One of my readers has a regular get-together with friends who have martinis and touch up their color or get haircuts (Okay, maybe the combination of gin and scissors makes me a little nervous, but that's just me. And we know that even a bad haircut pales in comparison to bad physical and mental health brought on or exacerbated by social isolation!)

You could try a rotating movie night, bowling, whatever works to keep you feeling connected to your pals. Izzy Rose of Stepmother's Milk is a big proponent of Girl's Night Out — check out her website for suggestions.

Yes, your spouse is a great person. But research shows that couples who don't make the extra effort can become isolated in their marriages — marooned together in essence (Gerstel and Sarkisian, "Marriage Reduces Social Ties," paper for the Council on Contemporary Families, 2007). This can be especially maladaptive for stepcouples, since they may experience aggravating fractures and differences in opinion in their parnterships for the first several years and even longer. Getting out with friends can be a great release and rejuvenator for them, a way to step away from their differences, connect with friends, and feel supported in fundamental and, it turns out, life-altering, if not life-saving, ways.

That's right. It turns out that friends are the new glass of red wine. Or the new dark chocolate. Or the new green tea. So indulge in friendship, without guilt.