Damon, who met Barosso while she was working in Miami's Crowbar Club, has bought a house nearby where they and her seven-year-old daughter Alexa will live after they are married later this year. "I'm with this woman and it's great," he grins. "I'm really happy."
He is in the vanguard of a growing number of Hollywood stars who are looking for their lifetime partners among the ranks of what Elizabeth Hurley calls "civilians", and the Hollywood film industry newspapers describe as "non-pros". More and more, as celebrity marriages crumble under the combination of publicity and paparazzi, the rich and famous are finding happiness with partners unknown to fans, photographers and anyone outside their immediate circle. If Julia Roberts' A-list actress and Hugh Grant's bookstore owner made it work in Notting Hill, why shouldn't it work in real life, too?
"A marriage has a far better chance of working if one of the partners is not a celebrity," says the Hollywood analyst Ron Krueger. "The odds are all against a marriage between two celebrities lasting any length of time."
A quick scan through the names of some of the literally hundreds of two-star marriages that ended in tears proves his point. And you don't have to go as far back as Elizabeth Taylor and Richard Burton. Alec Baldwin and Kim Basinger; Tom Cruise and Nicole Kidman; Dennis Quaid and Meg Ryan; Jim Carrey and Lauren Holly; Helen Hunt and Hank Azaria; Bruce Willis and Demi Moore; Angelina Jolie and Billy Bob Thornton; Renee Zellweger and Kenny Chesney; Uma Thurman and Ethan Hawke...
"The list is endless," Krueger says. "They have to deal not only with each other's egos but the intrusion of photographers, television cameras and all the other things that go with being a star - agents, managers and publicists all having their say and, of course, the demands of work schedules that can see them both separated for weeks and months on end.
"On top of that, they are usually working in close proximity to other very attractive and usually available celebrities. On balance, it seems that someone in the limelight is better off with a partner who is not involved in show business."
It is a formula that has worked well for Meryl Streep, who has been married for 26 years to a sculptor, Don Gummer, and has four children with him. Meanwhile, the former Friends star Lisa Kudrow lives a low-profile life with Michel Stern, her French advertising-executive husband of 10 years. "The most successful Hollywood couples are those in which one party is comfortable taking a backseat," says the psychologist Courtney Johnson, director of research at Tickle, the online social network.
Two of the Desperate Housewives cast are following his advice. Both Marcia Cross and Nicolette Sheridan are romantically involved with men who have nothing to do with acting. "His name is Tom Mahoney, he's a homebody and he's not in showbusiness," said Marcia of her new man. The Paris Hiltons of the world would probably be appalled, but red carpets, premieres and parties do not feature prominently in Marcia and Tom's lives. "We just like to be at home together, watch a movie or play Scrabble," she said. "He makes me very happy."
Nicolette Sheridan's fiancé, the Swedish-born Nicklas Soderblom, is a fitness instructor. "He handles the fact that I'm famous because of Desperate Housewives remarkably well," says the British-born actress. "He is very supportive of me and sometimes when we're skiing he'll even let me win on the downhill racing course."
Clint Eastwood's complicated love life included a marriage and divorce from his wife Maggie and romances with several actresses before he met and settled down with a local television news reporter in his hometown of Carmel, California, named Dina Ruiz. They have been married nearly 10 years.
So where are the best spots to bag a celebrity if you're looking for a Hollywood husband or wife? Waitressing is definitely the best bet for women. Jack Nicholson and Bruce Willis have both had long-running relationships with waitresses, and Nicolas Cage met his third wife, the 20-year-old Alice Kim, when she was a waitress in a Los Angeles sushi restaurant where he and a group of friends were eating. They were married in July and she is expecting a baby. It was Cage's first non-celebrity wedding, having previously been married to the actress Patricia Arquette and Elvis Presley's daughter Lisa-Marie Presley.
While they can expect a life of luxury, civilian spouses can no longer expect to walk away from a failed marriage with a massive fortune. Pre-nuptial agreements are now routine in Hollywood and while some contain stringent "no pay" clauses, others usually limit the spouse to a certain amount of money - usually $1m (£567,000) - for each year the marriage lasts.
One of the first to introduce an "escape clause" was the late Steve McQueen who, when he was divorced from Neile Adams in 1972, found himself facing a $3.5m alimony bill. When he later married Ali MacGraw they signed contracts absolving them from divorce settlements.
Other stars were not so canny. Clint Eastwood's wife Maggie received a $35m settlement in return for the actor's freedom to be with actress Sondra Locke. Later, Locke, too, successfully sued him for $10m; and when Kevin Costner divorced wife Cindy Silva, his college sweetheart and the mother of his three children in 1994 after a 16-year marriage, it cost him a staggering $80m. Michael Douglas, too, had to pay up to get out of his marriage to his wife Diandra when he wanted to marry Catherine Zeta-Jones. When she finally agreed to divorce him it cost him $70m.
There are no guarantees of marital bliss, even if one partner is unknown and happy to play a supporting role. Some marriages between stars and civilians are over before the confetti hits the ground. Drew Barrymore married Jeremy Thomas, the British owner of a Beverly Hills bar, in March 1994 after a six-week courtship. They separated a month later. The model Christie Brinkley married a property developer, Richard Taubman, in December 1994. "We want to be together all the time," she said. When they split six months later Brinkley sued him for £1m. Robin Givens, the television actress formerly married to Mike Tyson, went on to marry her tennis instructor, Svetozar Marinkovic on 22 August 1997. They separated the same day.
"Famous or not, rich or poor - sometimes it just ain't never going to work," shrugs Krueger.Reuse content