"To have been married for the amount of time that we have, you know, it's always hard work," he tells Lisa in the preview of Sunday's episode, which will air this weekend.
"It becomes a little more complicated," he added.
Earlier this year, Beckham's wife touched on their marital dramas in her British Vogue cover interview.
"People have been making things up about our relationship for 20 years, so David and I are pretty used to ignoring the nonsense and just carrying on as normal," she said.
"But these things have a wider effect on the people around us, and that's unfair."
"We both realize that we are stronger together than we are as individuals. Would either of us be in the position that we are in now had we not met and been together all those years ago?" she added.
"We are much stronger—the six of us—than we would be if we were individuals. We respect that family bond, and that is key."
The Beckhams are set to come to Australia with their entire family for the Invictus Games - of which the English football star is an ambassador for.
The fashion designer, 44, admitted in her Vogue chat that she's very excited about the trip.
"The only time I've been [to Australia] before was with the Spice Girls, 24 hours in Sydney and Melbourne,"she shared.
"When you're young and travelling the world like that, you'd sit in your hotel room and watch TV. When you're older, you want to get out and see things."
This article originally appeared on WHO.