Dr. Michelle Golland: Tipper and Al Gore aren't alone in choosing to end their 40-year-old union. The phenomenon of "The Gray Divorce" is growing. More and more 50-plus men and women are deciding to end their decades-old marriages. Some say it's due to the economic freedom that many women now enjoy; others credit Viagra, because it has helped create vastly new sexual experiences for older adults. Sixty may be the new 40! 

A May 2004 survey conducted by the AARP found that women initiated 66 percent of these gray divorces -- often blindsiding their husbands. 

The men who left marriages after many years often cited another relationship as the cause, while women left because they had reached a breaking point in an often-unhappy and difficult marriage. Both men and women cited the desire for freedom and a new identity as being pivotal in their decision to leave a longstanding marriage. Many of these couples also felt they needed a greater sense of meaning and fulfillment in their lives -- and obviously believed that was unattainable with their current partner.

In the last three decades, marriage has changed more than it had during the preceding 3,000 years. The marital union went from being a dependent partnership based mostly on economics to being mostly an equal union that is expected to provide emotional, sexual and financial fulfillment. Now more than ever, couples today want it all: economic equality, deep emotional commitment as partners and parents, and sexually satisfying lives. It's a lot to expect from one person -- especially when we haven't really been told how to have all of that (and certainly didn't see our parents having it, either).

The Baby Boomers are turning 60 and are facing retirement in large numbers. This transition from hard work to working less can destabilize a marriage in many ways. Al and Tipper Gore have cited "growing apart" and "leading separate lives" as culprits in the demise of their marriage. This is not at all surprising, considering their age, the age of their children and their busy lives. It's often the shared story of raising a family that holds couples together -- and when that starts to change as kids go off to college and create their own families, couples may be at a loss as to what to "do" next together.

A long-term marriage that survives decades is an ever-evolving relationship with a true life of its own. Together, the couple needs to invest time and energy into their coupledom -- not just their individual lives. The key is to discover new common goals for the future, whether they be traveling or new hobbies. 

The main goal is to have many "marriages" -- each different, each needing work, but each of them in the arms of the same person. The time and effort required to sustain a long and connected marriage is well worth it. It is imperative to reflect back on why you first fell in love with your partner; those early connections don't ever need to go away.

We just need to remember them more often.