You may want to rethink that second walk down the aisle if you are approaching retirement, and counting on income from Social Security.

If you're eligible to collect benefits on your ex-spouse's record, you will no longer be eligible for those benefits if you remarry.

That rule, plus others, is one of the reasons financial advisors like Stacy Francis, president and CEO of Francis Financial in New York City, sit down with savers to plot out a careful strategy when it comes to claiming Social Security.

Knowing these strategies becomes more important with the rise of gray divorce. The divorce rate for adults age 50 and over has nearly doubled in the past 25 years, according to data from the U.S. Census Bureau.

To be eligible to claim on your ex-spouse's Social Security benefits, whereby you receive up to half of their benefit amount, you must have been married at least 10 years and be at least 62 years of age.

You have the ability to choose between your own Social Security benefit or your ex-spouse's. Once you remarry, however, that choice is gone.

"This is where it pays to live in sin," Francis said. "If you get remarried, generally you can't collect on the benefits of your former spouse."

That changes if your second marriage ends because you get divorced, the marriage is annulled or your second spouse passes away.

At that point, if you were married to each spouse for 10 years or longer, you can choose between the two spouses' benefits, Francis said.

The benefit amounts do not change if more than one ex-spouse claims on one individual's records. Francis said she knows of one man whose four ex-wives were all eligible for the same spousal benefits on his record.