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Though Fergie, 37, and husband Josh Duhamel, 39, have been together for nine years, there is one thing the longtime couple can't escape -- the constant infidelity rumors surrounding Duhamel.

In 2009, tabloids alleged that he had a fling with an Atlanta stripper while filming Life As We Know It just 10 months into their 2009 wedding. Shortly after, various women made similar affair claims, though Duhamel and his lawyer vehemently denied any infidelity.

"It was difficult," the Black Eyed Peas singer admits to Oprah Winfrey about the highly scrutinized time in their marriage during an interview for Oprah's Next Chapter.

Video: Fergie Expresses Concern for Husband Josh Duhamel's Hometown

But according to Fergie, it also made them stronger.

"When you go through difficult times, it really makes you stronger as a unit, as a partnership. It does for us, anyways. Our love today is a deeper love, definitely. We're stronger today definitely because of anything difficult that's happened with us," she says. "We deal with it, we communicate; communicating's the most important thing."

Video: What Turns Fergie On About Husband Josh Duhamel

Fergie and Josh are still married today, and will be celebrating their fourth wedding anniversary in January.

Oprah's Next Chapter featuring Fergie's full interview airs October 21 at 9/8c. on OWN.