Why Jamie-Lynn Sigler kept her multiple sclerosis secret for 15 years

'Sopranos" and "Entourage" star Jamie-Lynn Sigler has been keeping a secret for 15 years: She has multiple sclerosis.

The 34-year-old actress revealed her MS diagnosis to People magazine, which also featured photos from her wedding last weekend to Cutter Dykstra, who plays for the Washington Nationals' minor league team.

Sigler was diagnosed around age 20 but hid her illness while starring as Meadow Soprano (Tony Soprano's daughter) on HBO's "The Sopranos." The series ran from 1999 through 2007.

"Sometimes all I needed was like five or 10 minutes to sit and recharge, but I wouldn't ask, because I didn't want them to be suspicious," Sigler said. MS is a chronic disease that affects the central nervous system. While symptoms greatly vary, it can result in mobility issues, vision problems, muscle control and extreme fatigue.

Why did Sigler hide her diagnosis for so long? She told People that she simply wasn't ready: "You'd think that after all these years, somebody would be settled with something like this, but it's still hard to accept," she said.

According to the Multiple Sclerosis Association of America (MSAA), acceptance is difficult for many people with MS, because the symptoms differ so widely from person to person.

"It could cause discomfort and unease, not knowing how MS may affect them," said Angel Blair, a client services specialist at MSAA. "Living with that instability can be worrisome . . . it's hard to accept the diagnosis."

Sigler also isn't the first celebrity to second-guess disclosing the disease. Talk show host Montel Williams found out he had MS in January 1998 but said he didn't go public with it n until eight months later, when a tabloid was going to run a story about his diagnosis.

Sigler credits her new marriage (along with her and Dykstra's 2-year-old son) with giving her the strength to come forward.

"I don't want to hold a secret where it feels like I have something to be ashamed of," she told the magazine. "It's part of me, but it's not who I am."