Jamie Lynn Sigler on Keeping MS Battle Secret & Christina Applegate Friendship (Exclusive)

Jamie Lynn Sigler is telling all in her candid, confession-filled new memoir “And So It Is,” sitting down with “Extra’s” Terri Seymour to talk about the book. 

She opens up about why she felt she couldn’t share her MS diagnosis at first, explaining it was "because I had placed all these labels on myself internally, by the time I got MS it was like, ‘Oh, my God, I cannot share this.' And unfortunately, that was my biggest battle and one that I decided I had to go through alone. You know, for 15 years."

 She only told her late “Sopranos” co-star James Gandolfini.

Sigler said, "James always protected me. He was like a father, you know, he was a father figure. He felt very safe. There was a breaking point during filming Season 5 where my marriage was falling apart and MS really started to manifest and I was not doing my best at work. They suggested I have an acting coach.”

She said of James, “He pulled me aside on set one day and said, 'Something is going on and I would like you to tell me.’ And that's when I told him.”

Today, Jamie Lynn is not in remission and still bravely battling MS.

"My circumstances have not changed,” she said. "I live in a disabled body. I have daily struggle. But I am the most confident and happy that I've ever been because of the healing work that I've been able to do."

Jamie Lynn is now married to Cutter Dykstra and they share two sons.

She recalled a very scary ordeal that happened while writing the book, when her oldest on Beau was hospitalized with a virus that left him fighting for his life. 

Sigler said, "There was a moment where he was not waking up out of anesthesia because of a procedure. And I could just tell that this nurse was worried about what was going on. And she said to me, 'Mom, I think it would be a good idea to call him. Call his name. call him back.’”

She continued, "And it was like in that moment, like I say in the opening of the book, it's like all of my past hang-ups about asking for help and being a people pleaser and were not calling attention to myself like completely dissolved. I opened myself up radically to God and my friends and everything and just like screamed his name and thankfully he woke up a few minutes later.”

How is Beau doing today? She said, “He’s great."

Plus, she talks about her friendship with fellow MS warrior Christina Applegate and sharing their health journeys on their podcast “MeSsy.”

The star said of Christina, "She just really was like, especially on ‘MeSsy,' like 'Jamie, we're going to say how it is. We're going to say how this affects us. We're not going to be afraid of how it lands.’”

She said, "We've got each other's back… We intimately understand.”