The interview, which will air Wednesday on U.S. morning show "Today," was Boyle's first TV interview since she became a global Internet and TV sensation with millions of fans. Transcripts of the interview were released on Monday.
When the church volunteer from Scotland failed to win the final of "Britain's Got Talent," she became ill and was treated for exhaustion at a London clinic.
"The impact, like a demolition ball. You know, and anyone who has that kind of impact -- finds it really hard to get a head around it," Boyle told interviewer Meredith Vieira of the "Today" show.
"I've got to be honest here," Boyle said. "I guess I had to get my head around it, but through the -- the guidance of a great team, and they are very good, I was able to see that in perspective and really turn that around a little."
Boyle is at work on an upcoming album, under the direction of Simon Cowell, the sharp-tongued judge from singing competitions "American Idol" and "Britain's Got Talent."
Cowell created "Britain's Got Talent" and its U.S. spin-off, "America's Got Talent."
The 48-year-old Boyle's April rendition of "I Dreamed a Dream," her first and most popular performance on "Britain's Got Talent," attracted 275 million video views on the Web and made her an global star.
"Being plucked from obscurity is a bit like, you know, going on a long journey," Boyle said. "You don't know what's going to happen. You don't know how it's going to end. I don't want it to end."
During her rise to fame, media outlets commented on Boyle's dowdy and unglamorous appearance, but she had a new haircut for her interview with Vieira, prompting the newscaster to compliment Boyle by saying, "I'm loving the hair."
(Reporting by Alex Dobuzinskis: Editing by Bob Tourtellotte and Todd Eastham)
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