Warren Buffett turns 88, but he's also celebrating one of the most important decisions he has ever made

Berkshire Hathaway CEO Warren Buffett believes making money means nothing without having another person, such as a spouse, to share the wealth with. Thursday, he's celebrating his 12th wedding anniversary with his wife, Astrid.

"It's much more fun achieving things in life with a partner, there's no question about it," Buffett told Forbes. "It's really a huge advantage from a personal standpoint to have a wonderful partner."

"That's true obviously in marriage, I mean that's the most important decision that you make," he added. "Who you marry, which is the ultimate partnership, is enormously important in determining the happiness in your life and your success and I was lucky in that respect."

Scientific research backs up Buffett's advice. A study by Carnegie Mellon University found that people with supportive spouses are "more likely to give themselves the chance to succeed."

Researchers studied 163 married couples and found that those with supportive spouses were more likely to take on big challenges. Those who accepted those challenges reported experiencing more personal growth, happiness and psychological well-being just a few months later.

Buffett told Forbes that his first wife, Susan Buffett, was one of his "greatest teachers," along with his late father, Howard, and late mentor Benjamin Graham.

Susan died in 2004. She had been the 17th richest woman in the world, worked as a director for Berkshire Hathaway and served as the Buffett Foundation's president.

In 2006, Buffett remarried to longtime friend Astrid Menks in a notably low-profile wedding held on the same day as his 76th birthday. Buffett, dressed in his business suit, and Menks, wearing a silk top and white pants, held a small ceremony at Buffett's daughter Susie's house in Omaha, Nebraska. Buffett's sons were out of the country, so the only other people there were Susie, Menks' sister and the judge who officiated during the 15-minute ceremony.

Though you may not have a choice in determining how you were born and raised, Buffett said, "you have something to say about who you marry."

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This is an updated version of a previously published article.