Jamie-Lynn Sigler and baseball player Cutter Dykstra married on Jan. 16, 2015, in Palm Springs, Calif. (Michael Kovac/Getty Images for Art of Elysium)

“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 drama 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, along with the brain and spine. While symptoms greatly vary, it can result in mobility issues, vision problems, muscle control problems and extreme fatigue.

[Reliable Source: Jamie-Lynn Sigler and Cutter Dykstra engaged]

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. The unpredictability of the disease — especially given that it affects people in wildly different ways — is often why people struggle to come to terms with the illness.

“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 the information until eight months later when a tabloid was going to run a story about his diagnosis.

“I had not told my children, my parents or even the company that syndicated my show … because as soon as you say you are ill in this country, people automatically assume you are weak, and in my profession, television, we don’t tolerate weakness,” Williams said in an interview with WebMD. “The reason why I hid my diagnosis is because I thought if I came forward, I’d lose my job. I thought I’d lose my family.”

Reality star Jack Osbourne, who started a campaign to raise MS awareness, echoed similar sentiments when he was diagnosed: “I think it’s that probably people assume once you’re diagnosed, you’re no longer an able-bodied individual,” he said. Michaele Salahi, star of “Real Housewives of D.C.,” also didn’t tell anyone that she had MS: “No one wants to be seen as sickly. And I didn’t want to be pitied,” she told People.

It’s understandable that people — especially in the public eye — may feel that way, especially if it could affect their work and livelihood. “I think at times, especially if they feel like it makes them vulnerable in any way or they could potentially be viewed differently from the way they were before, that can cause concern and hesitancy in wanting to disclose,” Blair said.

Blair added that misconceptions about MS may also play a part. For example, someone may have known a person with MS who had trouble walking and assumed that it’s the same with each MS case — when in fact, it’s different with each diagnosis. “Unfortunately, some people may not be educated or familiar with MS … so some feel they would be viewed differently or negatively at times, especially within the employment field,” Blair said.

Meanwhile, Sigler said that her “Sopranos” co-star, the late James Gandolfini, was very supportive when he found out about her diagnosis. She 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 or have something to hide,” she told the magazine. “It’s part of me, but it’s not who I am.”

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