Back in January Oprah Winfrey kicked off the year on a triumphant note with the opening of her $40 million Leadership Academy for Girls-South Africa. Her talk show was enjoying a successful 21st season, and as she neared her 53rd birthday, she appeared fitter and healthier than ever. "This," she proudly declared at the school's opening, "is everything I have ever worked for."

Fast forward 10 months, and 2007 is shaping up to be the daytime queen's annus horribilis. Plagued with personal setbacks—among them the accidental death of her beloved Golden Retriever Gracie in May and a recently revealed thyroid condition—Winfrey is currently weathering the unthinkable: allegations of abuse at her prized school, which offers a free education to 148 impoverished girls in the seventh and eighth grades. She flew to South Africa for a meeting with students' parents on Oct. 27. "I've disappointed you," a tearful Winfrey—herself the victim of childhood abuse—told the parents, according to South African newspaper Rapport. "I'm so sorry." As her best friend Gayle King told PEOPLE of Winfrey's reaction to the crisis: "Heart-wrenching doesn't do it justice."

It is a shocking turn of events at the deluxe boarding school, where the students affectionately call their patron Mama Oprah. Although authorities have released few details of the ongoing investigation, police spokesman Lungelo Dlamini confirms that there are multiple allegations of abuse. Rapport reported that the incidents included sexual and physical abuse, but police declined to comment on the nature of the misconduct. At the center of the investigation is a dorm parent who has been fired, and Head of Academy, Dr. Nomvuyo Mzamane, had been put on paid leave. Winfrey "is deeply concerned. She will get to the bottom of this," says Roger King, Chairman and CEO of the CBS Television Distribution Group, the distributor of her show. "She is working on finding out what happened."

Controversy around the school actually began swirling earlier this year. Within months of opening, some family members were complaining about the school's strict policies. The parents of a student who left the academy told PEOPLE in September that they were permitted to speak with their daughter for just one hour by phone each week. (A rep for Winfrey says students generally call or visit family on the weekends.) Their daughter complained of being "ill-treated" by her dorm mother, the student's mother added, because she came from a different area of the country than the woman. A source who works with several African children's charities says abuse is widespread among many children's institutions overseas and that the school's troubles are not entirely unexpected. Notes the source: "These are unintended consequences of good intentions."

No one would doubt Winfrey has had the best of intentions all along, even as it has been a difficult year for the talk-show icon, who was heartbroken in May after the sudden loss of 2-year-old Gracie. In the days that followed, "she was the one who was most devastated," says dog trainer and friend Tamar Geller, "and yet instead of breaking down and falling apart, she persevered with spirituality."

It was around that time that Winfrey began to feel "so exhausted, I was numb," as she put it in October's O, The Oprah Magazine. She was diagnosed with hyper- and hypothyroidism (see box), conditions that spurred a 20-lb. weight gain and inevitable speculation in the tabloids. "I read a story that said, 'Oprah comes clean about the thyroid'—like she was trying to hide it," says King. "It implies that it was something really bad. But Oprah's very open. She's going to be okay."

Likewise, other friends and colleagues say that Winfrey, whose show still rules the daytime ratings, will endure. Although the past few months "have been very draining," says a source at O who works closely with Winfrey, "she will rebound. She always says, 'Live and learn.'" Adds Geller: "We all have devastating things happen to us ... but with Oprah, as soon as something happens, she jumps in headfirst and rolls up her sleeves and deals with it."

  • Contributors:
  • Reported by Marcelle Katz/Cape Town,
  • Simon Perry/London,
  • Sharon Cotliar/New York City,
  • Liz McNeil/New York City,
  • Jeffrey Slonim/New York City,
  • Linda Marx/Miami.