Pop superstar Madonna married director Guy Ritchie because he was a "challenge" - and she is easily bored when it comes to love.

The Material Girl's eight-year marriage to the filmmaker came under intense scrutiny last month (10Mar08) when the Ritchie failed to show up at New York's Rock & Roll Hall Of Fame induction ceremony, where Madonna was honoured.

But the singer denies the relationship is under threat, instead insisting the pair keep each other mentally stimulated with their "tough" personalities.

She says, "I had to marry someone as tough as me. Guy's definitely tough, he doesn't give in. But he's obviously been put in front of me to teach me things and vice versa."

"I had to marry a challenge because otherwise I would just get bored. Whatever else Guy is, he's never boring." (CAM/WNTMI/JC)

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