LOS ANGELES (Reuters) - Actress Kirstie Alley described on Wednesday how she fell in love more than 20 years ago with John Travolta, and rejected widespread Hollywood speculation that the "Grease" star is secretly gay.

Alley, former star of the 1980s TV comedy "Cheers," told ABC television journalist Barbara Walters that she fell for both Travolta and actor Patrick Swayze in the 1980s, although their romances never got physical.

Alley, 61, said she was attracted to Travolta while the pair were making the 1989 movie "Look Who's Talking," calling him "the greatest love of my life."

"Believe me, it took everything I had inside, outside, whatever, to not run off and marry John and be with John for the rest of my life," Alley told Walters in an interview broadcast on breakfast TV show "Good Morning America."

Asked by Walters to comment on persistent rumors about Travolta's sexuality, she said: "I know John with all my heart and soul. He's not gay."

Alley added: "I think in some weird way, in Hollywood, if someone gets big enough and famous enough, and they're not out doing drugs and they're not womanizing, what do you say about them?"

Travolta was single at the time, but Alley was on her second marriage, so she never pursued her feelings, she explained.

Travolta later married actress Kelly Preston, his wife for the past 20 years. But the actor was the target of two lawsuits earlier this year, which were quickly dropped, from two male masseurs who claimed Travolta made unwanted sexual advances.

Alley, who talks more about her love life in her new book, "The Art of Men," said she fell for Swayze while they were filming the 1985 Civil War TV miniseries "North and South."

"We did fall in love. I was more willing to break up my marriage and I wasn't willing to break up his marriage," Alley said, explaining why the relationship failed to go further.

Swayze, best known for his lead role in "Dirty Dancing," died of pancreatic cancer in 2009 at the age of 57. He was married to dancer Lisa Niemi from 1975 until his death.

Alley has been married twice. Her second marriage, to actor Parker Stevenson, ended in 1997.