07/30/2010 06:18 am ET Updated Nov 17, 2011

The Real Reason Couples Divorce

Here's the real reason good marriages can go bad: If a scientist places two rats on a metal grid and then passes an electric current through the grid, every time the rats feel an electric shock they will attack each other. Likewise with humans: when life gets stressful, we instinctively pick a fight with our spouses.

Have you ever looked at your spouse and secretly wondered, "Did I choose the wrong mate?" Many of us marvel at how we could have felt such a powerful chemistry for our mates before we married, but later we catch ourselves daydreaming about divorce.

It's not our chemistry that failed us. Rather, humans have forgotten we are animals, and we share with animals a little-known, unconscious instinct to scapegoat those around us. That is what drives couples apart. But a simple awareness of our scapegoating instinct can transform how we view our marriages.

Scapegoating is an ancient defense mechanism in the brain that allows us to off-load our anxious reactivity onto others. Bestselling author and primatologist Frans de Waal describes our tendency to blame others as one of our least conscious, yet most powerful instincts. This displacement of blame happens so often, in so many animal species, that it must be hardwired in us, dating back thousands of years.

From a survival of the fittest perspective, scapegoating was a valuable adaptation. Back in our caveman days, a little bit of anxious reactivity was a useful survival instinct, because it triggered our fight-or-flight response and kept us on our toes.

But if too much anxiety overwhelmed our brains we might shut down--unable to hunt, gather or procreate. So scapegoating probably evolved to help us lighten our load of anxiety by off-loading it onto those around us, which cleared our minds to better focus on competing for scarce resources. The Blame Game is a primitive survival instinct.

Of course, blaming others for our suffering is nothing new. The term "scapegoat" comes from Hebrew and describes an ancient Jewish ritual of atonement during Yom Kippur. People believed God made them suffer as punishment for their sins.

So their atonement ritual involved two goats as symbols. One goat was sacrificed as a symbolic "payment" to God for the debt they had amassed by their sinning. The other goat (the "escape goat") was driven into the wilderness, symbolically carrying the sins of the people on his back. This was how people paid for their sins in order to free themselves from their suffering. That's why today, a scapegoat usually refers to an innocent person who is blamed for the suffering or wrongdoing of others.

So, here's the key lesson we can learn: When we criticize our spouses, we tend to believe we are pointing out true, objective faults. But in fact, blaming our spouse may just be our anxiety talking. As discussed above, people with higher anxiety are more likely to overreact, so spouses with high anxiety will have a greater tendency to fight-or-flee each other, which may lead to a downward spiral that sours their marriage. When the going gets tough, rats, humans and many other species scapegoat.

This is actually great news, because now we can give up searching for a Spouse-Upgrade. Our marriages will fare better when we let go of the illusion that the grass would be greener with a different mate.

Sure, we all know folks who would swear their ex-spouse was a dud and the chemistry they felt at first was dead wrong. But they may be kidding themselves. Their second spouse may have different traits, but the basic ways humans cope with anxiety--fight, flight or scapegoating--are always beneath the surface.

Until we become aware of our own anxiety and scapegoating instinct, we simply drag all of our baggage into our next marriage as well. That's why the divorce rate for second marriages is 60 percent, and for third marriages it's 73 percent. Things only seem different in a new relationship.

Marriage is a school for lovers, so contrary to popular belief, it's not about managing your partner. It's about managing your anxiety. This insight can help you accept yourself and your spouse as you are, for better or for worse, in sickness and in health. As my mother-in-law was fond of saying, marriage is not a "correctional institution."

So, I'm curious. How does my point strike you? Do you agree that the scapegoating instinct we share with animals may cause divorce? What has been your experience? What have you observed in the marriages of your friends and family?

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