Jamie Lynn Sigler's New Book 'And So It Is': Biggest Revelations

Jamie Lynn Sigler bravely revisited the ups and downs of her life in her newly released book, And So It Is….: A Memoir of Acceptance and Hope.

Published on May 5, the memoir explored Sigler's complicated relationship with AJ Discala, including the time she ended things with him after finding messages between him and his ex.

"I lost it. I snapped," she wrote. "Seeing red, I opened the shower door and started screaming. The words streamed out of my mouth, and I can barely remember them. I told him to leave. I fired him and I broke up with him in one sentence."

Although they split up, Sigler eventually forgave Discala and married him during a 2003 ceremony. She was 22 at the time, while he was 10 years older.

In her memoir, the 44-year-old actress theorized why her TV dad and costar, James Gandolfini, did not attend the nuptials.

"I can't say for certain why. He's not here, so I can't ask him," she wrote of Gandolfini, who of a heart attack at age 51 in 2013. "But Jim had always shown up for me. He'd come to see me in Beauty and the Beast with his son, Michael. The Jim I knew wouldn't have just skipped my wedding without a word or an excuse. Part of me wonders if maybe he didn't want it for me,"

When she introduced herself to her castmates as "Jamie Lynn Discala," the room was reportedly "completely silent" until Gandolfini shattered the awkward silence with an audible "ooof."

"It was clear: none of them were happy about this for me," she continued. "It would take me two long years to understand why."

The "Cry Baby" hitmaker shared further details about her toxic first marriage, which ended in 2006, in the memoir.

"I was only 20, trying to figure out who I was," she wrote. "He seemed to me then a lifeline, but I know now he was a big mistake. Untangling those contradictions has taken me years."

She also said of her ex elsewhere in the book, "I was in way over my head, and AJ seemed like the answer to all my problems. I realize now that he had no real connections, no music industry expertise, and no real knowledge. But at the time, I needed him, so I believed him. And so did my family."

During divorce proceedings, a longtime family friend who happened to be an accountant discovered that "hundreds of thousands of dollars" were missing from Sigler's funds, as Discala had allegedly been transferring funds every time she got paid from The Sopranos.

"The forensic accountant broke down what he believed had been happening," she penned. "I would be paid a certain amount per episode for the Sopranos, and that would go into my corporation account. The next day, a portion of that money would be moved to our joint account for living expenses. But then a week or so later, a much smaller but still sizable amount of that money from our joint account would be moved to a different account that I didn't have access to or know about."

Sigler admitted she still does not know what happened with the money "to this day," adding, "But I don't care anymore. That money is a chapter I want closed forever."

Sigler found love again when she met Jerry Ferrara on the set of Entourage. Even after she was diagnosed with multiple sclerosis, her then-boyfriend became her "anchor" and her "teacher."

"He tried to help me move away from that looped anxious thinking about what everyone thought about me," she wrote in the book. "He taught me that acting could be joyful, he reminded me of my talent, and he lightened my darkness. He taught me that someone who loved you wouldn't just leave you if you fell apart."

However, the autoimmune disease soon took a devastating toll on their relationship as she dealt with the "worst flare of MS symptoms yet."

"I found myself picking fights with Jerry just to push him away," Sigler continued. "I think that I was trying to spare him from what I knew I was about to enter: a deep depression spiral, and I didn't want to take him with me. He was too good for that. He deserved more."

In the memoir, Sigler called her sole album, Here to Heaven, her "biggest career mistake."

"There was no one guiding me. I didn't know what I was signing myself to. It was like a freight train that ran away and I couldn't do anything about it," she explained.