WHEN FORMER ALLY MCBEAL STAR COURTNEY THORNE-SMITH, 33, received a marriage proposal from her boyfriend, genetic scientist Andrew Conrad, 36, on October 23, 1998, she had mixed emotions. On the one hand, she said yes. On the other hand, Thorne-Smith could not even begin to make preparations because "the idea of planning a wedding . . . caused my entire body to shut down and my brain to go into full-fledged denial." Perhaps her organs were trying to tell her something.
     On January 4, seven months after she and Conrad pulled together for an unusual wedding on the Hawaiian island of Lanai, they announced that they were splitting up. "There are no third parties involved," she said. "We remain very good friends and will share custody of our dogs."
     Through March 23, Thorne-Smith also has custody of InStyle magazine's special weddings issue, from which she smiles out contentedly in a Les Habitudes dress. The cover photo is a monument to a relationship that was growing increasingly strained. Thorne-Smith met her spouse in 1997 through her sister, Jennifer. The two dated for 18 months before getting engaged. Thorne-Smith, though never overweight, admits she was worried about fitting into her bridal gown. As she told Us weekly in December, she struggled with her weight issues during her tenure on Ally, from 1997 to 2000. "The amount of time I spent thinking about food was insane," she says. Thorne-Smith dieted and lost 15 pounds, but by the end of last season she was exhausted and asked to be released from her contract.
     In December 1999, Thorne-Smith invited family and friends to a four-day party in Hawaii from May 31 to June 3, 2000, and said she and Conrad would get married by themselves beforehand. But the couple arrived on Lanai with no intention of tyong the knot. "Andy and I had convinced ourselves that the fact that we 'felt' married was enough," she writes in InStyle. Then Thorne-Smith had a change of heart. "Many of the people I love most would be in one place for four days," she writes, "and I wanted to share my wedding day with them." Rushed preparations were made, and on June 1 she walked down the aisle as guests hummed an impromptu, out-of-tune rendition of "Here Comes the Bride."
     At first, Thorne-Smith felt good about her decision, she writes: "When the minister announced us as 'Mr. and Mrs. Andrew Conrad,' and we turned around and saw so many happy (relieved?) faces, I knew we had done the right thing by getting married in front of our loved ones." In December, Thorne-Smith told Us weekly she could see herself starting a family with Conrad.
     But the mood didn't last. Later that month, she spent a week with her mother, Lora, at an Arizona spa. And last week she said the marriage was over. Thorne-Smith, a spokesperson said, would be focusing on writing, traveling and perhaps competing in a marathon.

Courtney Thorne-Smith isn't the only star whose marriage was over before the rice hit the ground.
• Robin Givens and tennis instructor Svetozar Marinkovic married on August 22, 1997, and separated that same day. Givens filed for divorce on December 19 of that year.
• Dennis Hopper and Michelle Phillips married on October 31, 1970, and divorced eight days later.
• Carmen Electra and NBA star Dennis Rodman married on November 14, 1998; Rodman sought an annulment nine days later, claiming he was drunk at the time.
• Producer Robert Evans (Chinatown) wed former Dynasty star Catherine Oxenberg on July 12, 1998, four days after they had met, and announced they were seeking an annulment 12 days later.
• Patty Duke wed rock promoter Michael Tell on June 24, 1970, and filed for divorce 13 days later.
• Drew Barrymore wed bar owner Jeremy Thomas om March 20, 1994, after a six-week courtship. "I'm so lucky to have met this person," Barrymore said. They separated on April 19.
• Charlie Sheen wed model Donna Peele on September 3, 1995; they divorced on November 19, 1996.
• Shannen Doherty wed actor Ashley Hamilton on September 24, 1993, two weeks after they had met. Although Doherty threatened Hamilton with a gun, Hamilton said, "I really do love her and I'll always love her. I wouldn't marry anyone else." The separated in February 1994, and Doherty filed for divorce on April 7, 1994.
• Janet Jackson and R&B singer James DeBarge eloped on September 7, 1984, in Michigan and had the marriage annulled in March 1995.
• Christie Brinkley wed real estate developer Richard Taubman on December 22, 1994. "We want to be together all the time," she said. When they split on July 26, 1995, Brinkley sued him for $2 million.
• Jim Carrey and Lauren Holly married on September 23, 1996, after meeting on the set of the 1994 movie Dumb and Dumber. They separated on June 25, 1997.
• Elizabeth Taylor and Richard Burton were first married on March 15, 1964, and divorced 10 years later. They married again October 10, 1975. Burton divorced her again on July 29, 1976. Taylor's first marriage, to hotelier Nicky Hilton, had lasted eight months.
• Helen Hunt and Hank Azaria married on July 17, 1999, after dating for nearly five years. They said in August 2000 that they had been separated for months.
• Marilyn Monroe and Joe DiMaggio married on January 14, 1954, and divorced on October 27, 1954.
• Alyssa Milano and musician Cinjun Tate married on January 1, 1999. They separated on November 20 of the same year.