NICOLE KIDMAN IS A FREAK ON THE DOWNLOW!

Nicole Kidman is opening up her bedroom door.
In the December issue of British GQ, the 42-year-old actress discusses all the different types of love that she's experienced.

"I've explored obsession. I've explored loss and love in terms of being in a grief-stricken place, I've explored strange sexual fetish stuff, I've explored the mundane aspect of marriage, and monogamy," she said.

Normally tight-lipped, Kidman reveals truths about her past marriage to Tom Cruise. She admits that her agents advised her not to get married at the tender age of 19 because it would ruin her career.

"I know my agents at the time were like 'Do not get married! It will ruin your career!' and I was like 'But I'm in love,'" says Kidman, who stars in the new movie version of the musical "Nine." "All I know is that I wasn't someone interested in fame. And that's not why I got married. I wanted to work with people who intrigued me."

Her marriage to Cruise ended in 2001, after ten years and two children. Kidman married country singer Keith Urban in 2006 and gave birth to their first child last year.

But there are some topics that are still off limits for the Australian beauty. She won't discuss the reasons behind her split from Cruise.

"I want to honor that marriage for what it was, and there is nothing I would go into about that. I have never discussed the intricacies of it and I never will," Kidman says.

How serious is she at protecting her secrets?

The actress tells GQ that she even set fire to her early diaries after she married Urban.