Ashton Kutcher may have made his name by appearing in lightweight US TV shows, such as That '70s Show and films like Dude, Where's My Car, as well as fronting the MTV prank show Punk'd but he really hit the headlines when he pulled off the ultimate coup by marrying the world-famous film star Demi Moore.

Demi Moore brought a certain Hollywood pedigree with her to their relationship. Her breakthrough role came when she played the lead in the 1990 film Ghost, in which she starred opposite Patrick Swayze. The movie has grossed over 500 million US Dollars and is widely recognised as one of the finest films of the modern age. Its script is oft-quoted, its infamous pottery wheel scene is oft-repeated and its theme song, Unchained Melody is oft-sung in dimly-lit karaoke bars. Most of the movie-going public, however, would probably struggle to repeat a line from the script of Dude, Where's My Car.

When the pair started dating in 2003, the world looked on - bemused and puzzled, but tolerant, nonetheless. After all, in a world where Eddie Murphy can father a child with ex-Spice Girl Mel B and Michael Jackson joins in holy matrimony with Elvis' only daughter, Ashton and Demi's pairing was relatively small fry in the gossip columns. In fact, so accepting were we of Demi Moore and Ashton Kutcher's union, that soon we were holding them up as shining examples of modern relationship bliss.

Despite initial concerns over the longevity of Demi and Ashton's pairing, the public soon warmed to them. Ashton's activity on his Twitter account afforded their fans an insight into their married life; none more so than when he posted a picture of Demi in her knickers, bent over and doing some housework. The picture was accompanied by the message 'ssshhh, don't tell wifey'.

Demi brought three daughters with her to the relationship. Their father (and her ex-husband) was another Hollywood heavyweight, going by the name of Bruce Willis. A number of mainstream lifestyle magazines published articles proclaiming how positive and progressive Demi, Ashton and Bruce were, as they were pictured all together, with the children, at awards ceremonies, movie premieres and family days out. With their daughters' futures in the forefront of their minds, Bruce seemed happy to overlook the age gap between Demi and Ashton (she was 40 when they met, Kutcher was 25) and focus on forging a harmonious friendship with his ex-wife's new partner. The Willis-Kutcher agreement seemed, on the surface of things, to be the pinnacle of modern-living; after all, who needs revenge when you can pop out for a few friendly beers with your ex-wife's new toy boy?

This, however, was back in the early Noughties. The Bruce and Ashton portrait circa 2011 tells a different story entirely. In March 2011, both parents turned up to watch their daughter, Rumer Willis in her off-Broadway production of Love, Loss and What I Wore. Each parent had their respective partner on their arm. By September, though, the tide had turned, as Demi Moore found out about Ashton's recent infidelity. He allegedly had sex with a 23-year old Texan, named Sara Leal, on the night of his sixth wedding anniversary to Demi. It's not the first time that Ashton has been accused of being unfaithful to his actress wife but it was the first time that Demi decided that enough was enough and called in the divorce lawyers.

Hollywood gossip websites were quick to report on Bruce's angry response. Willis, according to internet rumours, summoned Ashton to a 'secret location' and tore strips off the shamed lothario; accusing him not only of embarrassing Demi herself, but of bringing undue attention to their three children. Ashton's response, apparently was to tearfully beg forgiveness and promise to be faithful forever more. Willis' advice to his former wife was that the couple should seek traditional counselling and not just Kabbalah counselling, as they had been doing up until that point.

Perhaps Ashton is concerned that his public profile would wane, if he were no longer a permanent Polaroid in the Willis-Moore family album. His career has taken a number of paths, but he has never received the critical acclaim, nor achieved the success that his wife has and, in many respects, he still lives in her shadow. He has, however, taken over Charlie Sheen's role in the sitcom Three and a Half Men. Public response to the replacement, though, has been muted; perhaps people are waiting to discover whether or not Kutcher cracks under the pressure of public scrutiny and goes the same way as Sheen, before casting judgement on his acting abilities.

Either way, the fate of Kutcher's marriage to Demi Moore hangs in the balance, thanks to his infidelity. And whilst Demi Moore's legions of fans across the globe scrape their jaws off of the floor in disbelief, Kutcher's seem largely happy to forgive his misdemeanour. Whether or not Demi will follow suit remains to be seen but is looking unlikely.

Visit the Ashton Kutcher, Demi Moore Divorce Facebook page

Ashton Kutcher and Demi Moore - A Marriage in Pictures Gallery