The average American marriage that ends in divorce lasts about eight years.

Bill and Betty Evans have been married for nearly 67 years.

"I probably asked her half a dozen times before she said 'Yes,'" Bill told Iowa's KCCI.com in a special Valentine's Day report.

The pair met on a naval base in Maryland in 1947 and tied the knot a few months later. Fast forward to today, and they have three children, four grandchildren, and five great-grandchildren.

Speaking to KCCI, Bill joked that he didn't think he'd live 67 years "let alone be married for that long." But he has, and he and his wife shared some of their secrets for a long and loving relationship.

Bill joked that he "learned early in life to say, 'yes, ma'am.'" He said the two rarely argue, but they do have "discussions" and have never made a "serious decision without consulting the other one."

"Cherish each other," he continued. "Respect each other forever. No matter what happens."

Of course it's one thing to hear that advice from somebody who just watched "The Notebook" and think they know it all. But to hear the advice from a couple who's still in love after 67 years of marriage is something else entirely.

As for how they plan to celebrate Valentine's Day, KCCI reports the couple will be enjoying a meal at their local Red Lobster, which happens to be Betty's favorite restaurant.

Follow Mike Krumboltz on Twitter (@mikekrumboltz).