Madonna and Guy Ritchie didn't have sex for 18 months as their marriage crumbled.

The couple - who announced last week they were separating, ending months of rumours - reportedly didn't get close beneath the sheets because the 'Hung Up' singer was too tired for love due to her gruelling daily 4-hour workouts.

A friend close to the pair said: "Guy got more and more frustrated as she spent nearly half the day exercising. When she did eventually get home she'd be too tired to make love.

"When the cracks first started to show, Guy would plead with her to spend more time with him but she wouldn't. She'd insist she did her four-hour workout. They've been apart so much in the last two years that their opportunities to make love would have been fairly limited. They've also been in separate rooms a lot after big rows so there wasn't any chance to make up."

It has also been claimed that Guy, 40, found 50-year-old Madonna's super-toned body a turn-off, and yearned for the soft, womanly curves she had when they first fell in love after meeting in 1999.

The 'RocknRolla' director is reported to have confided in a friend he was finding his superstar star spouse less attractive the more fitness obsessed she became.

The pal told Britain's News of the World newspaper: "After a few drinks one evening, Guy said it was like cuddling up to a piece of gristle. All the soft feminine tones had been replaced by the build of an athlete."

It has also been claimed the estranged couple did have a pre-nuptial agreement in place before they tied the knot at Scotland's Skibo Castle in December 2000.

Guy - who is believed to be worth £30 million - will reportedly receive around £12 million in cash, the pair's 1,200 acre Wiltshire estate and their London pub the Punchbowl in the settlement.

He cannot claim any of the £300 million fortune Madonna has amassed during their seven-and-a-half year union.

However, it is still not clear what the custody arrangements will be regarding the three children Madonna and Guy raise together - 12-year-old Lourdes, the singer's daughter with dancer Carlos Leon, son Rocco, eight, and adopted son David Banda, three.

(China Daily/Agencies October 20, 2008)