Idina Menzel: A Diva Rides on

Idina Menzel seems to have every child below the age of 10 under her spell – not that some of her biggest fans know quite who she is. Recently her son Walker, 4, “was at a party, and a bunch of little girls were there singing songs from Frozen,” says Menzel, who belts the megahit “Let It Go” as the voice of ice princess Elsa in the Disney blockbuster. “And he said, ‘Oh, my mommy sings songs from Frozen,’ And they said” – she affects an unimpressed voice – ” ‘So do our moms!'”

Not like Menzel does. This winter, as Frozen and “Let It Go” snowballed into international sensations – more than $1 billion at the box office, a Best Song Oscar, 165 million YouTube views – the Broadway veteran, 42, finally started to experience life as a household name. Then, on Oscar night, her name – well, not exactly hers; may “Adele Dazeem” rest in peace – became the world’s most famous moniker after John Travolta’s flub introducing her performance of “Let It Go.” In the months leading up to that moment, Menzel had been coping with a more painful upheaval: In December she and her husband, actor Taye Diggs, announced their separation after 10 years of marriage. Appropriately, her new Broadway musical, If/Then, is about a newly divorced woman at a crossroads in her life. All the attention “has been overwhelming at times,” says Menzel. “It’s been crazy. So I’ve just focused on the show.”

As she collapses on a sofa in a Brooklyn warehouse at 10 p.m. and digs into her first full meal of the busy day (brussels sprouts and a tomato salad), Menzel can only laugh at how her life has changed since Oscar night. “It’s been crazy. More people know me. But having a 4-year-old keeps me grounded no matter what else is happening.” All the accolades can’t give Menzel what she wants most at this moment. “If I could have one magic power, then it would be to be the baby whisperer and get my son to go to sleep at night,” she says with a sigh.

After making Walker breakfast each morning at her Manhattan apartment and taking him to school, she heads to the theater to prep for If/Then, the first show in which she’s been billed above the title. “My character isn’t sure where her life should lead,” says Menzel, and the play shows two paths she could follow, à la the movie Sliding Doors. For the actress, “being back onstage is like being back home.” Her big break came at another crossroads moment, in 1995, when she auditioned for a musical for Michael Greif, now the director of If/Then. “Although Idina wasn’t right for that part,” Greif says, “I knew she’d be great for Jonathan Larson’s new musical. She has an incredibly raw, open quality.” Larson’s show was the soon-to-be smash Rent, and Menzel was cast as bisexual anarchist Maureen Johnson. “It changed my life,” she says.

Not only did she nab a Tony nomination; she and costar Diggs fell in love and later married in 2003. Despite juggling demanding work schedules, at times on opposite coasts, the couple managed to make it work for a decade. “We go through tough times like everybody else,” she told PEOPLE last year. Now, Menzel says, “I’m doing okay. We’re doing good. Our focus will always be our son. We were together for a long time and grew apart, but we’re still close.”

She says she’s been leaning on family and friends, especially her younger sister Cara, 39, a teacher. “My sister and I are really close. Even though she’s younger, she was the first one to get married and have kids, so I’ve always gone to her for advice.” Menzel was raised on Long Island by Helene, a therapist, and Stuart Mentzel, a salesman, who split when Idina was 16. Menzel (who dropped the “t” to reflect the correct pronunciation of her name) dreamed of starring on Broadway from the start. As a teen she began singing at bar mitzvahs and weddings before enrolling at NYU as a drama major. But even once she found Broadway success, her path to stardom remained rocky. “When I was in Rent, I thought I could be a rock star,” she says. “I found out the music industry just didn’t think a theater singer could cross over.” More stage work followed, and in 2003 she landed her career-making role as Elphaba, the green-skinned witch in the Broadway hit Wicked, which earned her a Tony. In 2010 she reached an even wider audience with a recurring role on TV’s Glee, playing the mom of Lea Michele’s character.

While grateful for her legions of young fans, she admits to feeling restricted at times. “Sometimes I’ll want to say a curse word or tell a story at my concerts,” she says. “And I’ll see 10-year-old girls there dressed as Elsa or Elphaba, and I know I can’t just drop an F-bomb. But I’m a 42-year-old woman! I have stories!” Most of them, she says, are lessons she learned the hard way. “I’ve struggled with self-doubt, with learning to be okay in who I am,” she admits. “As I’ve grown older, I want to be the kind of person who is courageous, who takes risks. And I want to give back.” She already does that with A BroaderWay Foundation, an organization she created with Diggs in 2010. Each year, Menzel, Diggs and their theater friends host a 10-day camp to mentor “and help girls find their voice in life,” she says. She and Diggs plan to be back this summer, despite their separation. As for what happens next, if an unpredictable Oscar night has taught Menzel anything, it’s that things rarely go as planned. Luckily she’s learned to go with the flow. “If you follow your path and focus on love,” she says, “things will work out.”