VENICE: Elvis Presley's former wife Priscilla said the legendary rock star had been the love of her life, despite eventually leaving him, as a film about their turbulent relationship hit the Venice Film Festival.

"Priscilla", directed by Sofia Coppola, is based on her 1985 autobiography, "Elvis and Me", depicting her roller-coaster life with one of the most famous figures of the 20th century.

"It wasn't that I didn't love him. He was the love of my life, but it was the lifestyle that was so difficult for me," Priscilla told reporters in Venice ahead of the world premiere of the movie, which stars Cailee Spaeny and Jacob Elordi.

Priscilla Beaulieu met Elvis Presley in 1959 when she was just 14 and he was deeply homesick, stationed with the U.S. army in West Germany.

"Elvis poured his heart out to me in Germany, his fears and his hopes, the loss of his mother, which he never ever got over," Priscilla said. "People think it was the sex. Not at all. I never had sex with him. He was very kind, very loving, but he respected the fact that I was only 14 years old."

Elvis returned to the United States shortly after, but the two remained in touch and in 1963 he invited her to come and live with him in Memphis, where she finished school.

They got married in 1967, had a baby daughter, Lisa Marie, in 1968, and divorced in 1973, four years before Elvis died of heart failure, aged just 42. "We still remained very, very close," Priscilla said.

The film offers perhaps the darkest screen portrayal yet of Elvis as he relentlessly manipulates Priscilla, verbally abusing her and at times threatening her before seeking to make amends.

"It is very difficult to sit and watch a film about you and about your life and about your love," said Priscilla, 78, pausing a while as she struggled to overcome her emotions. "I think Sophia did an amazing job. She did her homework."

Coppola said she had leaned heavily on Priscilla as she put the film together. "I really tried to make the film from her point of view so we could go along on the journey with her," she told reporters.

Spaeny said she had also turned to Priscilla for help as she prepared to bring the often vulnerable character alive on the big screen.

"She was very generous with her time and she was very kind to me and supportive. And I think if I didn't have that, I would have had a much harder time," the U.S. actress said.

"Priscilla" is one of 23 movies competing for the Golden Lion award at the Venice festival, which runs until Sept. 9.