Being married to an international superstar like Tom Cruise is tough - at least according to his last two wives.

His most recent ex Katie Holmes filed for divorce after the marriage had "broken down irretrievably" for six months, and his second wife Nicole Kidman has been speaking out about what it was like to be married to and divorced from one of the most famous men on the planet.

Kidman, 45, talked about the "overwhelming" aspects of her marriage to Cruise, 50, in the latest issue of Harper's Bazaar, which features a gold-clad Kidman on its cover.

The actress said at the beginning of her relationship with Cruise she felt the pitfalls of gaining "fame by association."

"It was like, 'I'm here and I'm clutching onto your arm, and it all feels a little overwhelming and really strange.' ... And I was shy. Deeply shy. I didn't feel comfortable at all. But I felt very comfortable at home," she said.

Kidman recently talked with the Australian magazine Who about the depression she felt during her divorce from Cruise.

"I got married really fast and really young," Kidman said. "But I don't regret that because it got me [my children] Bella and Connor and I did have a fantastic marriage for a long period. Then when it didn't work out I had to really dig deep and find my way through depression. I have no regrets about all of it. It was all part of growing up."

But she told Harper's Bazaar that she has had no such issues in her marriage to 44-year-old country star Keith Urban, with whom she has two children, Sunday and Faith.

"He just gave me confidence," she said. "Through just being very kind to me and understanding me, opening me up to trying things, my sexuality, those sorts of things."