8 Most Shocking Revelations From Jennie Garth's New Book 'I Choose Me' — Including Her Substance Abuse Struggles and Drama With Tiffani Thiessen

Jennie Garth revealed her life story with unfiltered honesty in her new book.

In I Choose Me: Chasing Joy, Finding Purpose & Embracing Reinvention, Garth tackled the highs and lows of her life, including the most difficult chapters in her marriage to Peter Facinelli.

According to the Beverly Hills, 90210 alum, she nearly overdosed when her marriage to Facinelli began to break down. She recalled the time she drank and took anxiety pills and how she "thought swallowing a few of those would help take the edge off [her] desperate, broken heart."

She unknowingly called her best friend Liz while having "dark thoughts" in a hotel room in Phoenix.

"When she came to my room, I didn't answer," she wrote about her pal. "She pounded on the door, called me relentlessly, until finally she had to ask the hotel for help. They opened the door, and Liz saw me unconscious on the floor. She called 911 and I was rushed in an ambulance to the hospital, where I had to get my stomach pumped. I was out of the woods. At least physically. "

Reflecting on the events that led to her near-overdose, Garth said she and Facinelli attended a therapy appointment in Arizona, which she believed was an attempt to save their crumbling marriage.

"[The therapist] looked at me gently but without hesitation, and asked, 'Jennie, why do you want to be with someone who doesn't love you?' It was a statement that I will never unhear. The question stopped me cold," she wrote.

"It became clear to me why we were here. It wasn't to work on our relationship. He wasn't giving it one last try with the help of a new therapist. He had come here to end our marriage once and for all, in the presence of a third party," Garth continued. "I hadn't fully understood what he had been saying for the last few months. I had been clinging to hope, or disbelief, or denial. But now, in no uncertain terms, it was over."

The What I Like About You star called it her "last-ditch effort" to save them while their marriage "was breaking down, [or] had already broken down maybe."

"I suggested this appointment, and I was grateful that he agreed. It had been my last hope," she added in her new book.

Garth almost ended up the same way when she briefly split from her husband, Dave Abrams, in August 2017. At the time, she spiraled into depression and alcohol abuse, and her eldest daughter, Luca, even caught her harming herself with shards of glass.

"I was in my room smashing framed pictures of me and Dave, overcome by the pain," the 54-year-old wrote. "I was taking the broken glass from the picture frames and I was trying to cut myself with the jagged pieces. I was certainly not in my right mind."

The matriarch noted, "It was almost an unconscious act, a form of punishment."

Elsewhere in I Choose Me, Garth mentioned Beverly Hills, 90210 Season 5 newcomer Tiffani Thiessen as she opened up about the drama surrounding them.

"I immediately felt threatened and competitive," she admitted. "Just as I had with many beautiful female costars before. It took me a few days to realize that I was unconsciously perpetuating unhealthy patterns, patterns that our characters played out on the show."

Thiessen famously played Valerie Malone from 1994 to 1998.

"I apologized to her and told her I didn't want to be competitive, that I wanted to be her friend," Garth wrote. "And that's how we became best friends during her years on 90210. It was instinctual to lead with that defensive energy at first, but because Tiffani was forgiving and open to my apology, we were able to build something real."

While they maintained a solid bond after the show ended, they had a falling out that cost them their friendship.

"We're no longer close," Garth disclosed, adding, "While we were friendly, the connection we once shared wasn't there. I've come to see that some friendships are meant for a reason or a season, and ours was a meaningful one while it lasted."

The hit teen drama catapulted Garth to fame, but it also exacerbated her body image issues.

"I never imagined that stepping into a character's shoes would start to define how I saw my own reflection. When I began playing Kelly Taylor on Beverly Hills, 90210, I hadn't dealt with the body image issues in my real life," she shared in her book. "Those storylines — Kelly dieting, feeling insecure, being praised or scrutinized for her looks — were foreign to me. I approached them as an actress does: with imagination and curiosity."

Like her character, Garth reportedly "faced harsh judgments and struggled to maintain [her] mental health," while the messages on Beverly Hills, 90210 "began to blur the line between character and self." The show's competitive environment also made her feel judged on her appearance, leading her to compare herself to others and even seek approval from her male costars, including Brian Austin Green, Luke Perry, Jason Priestley and Ian Ziering.

In I Choose Me, Garth opened up about the head injuries she suffered on the set of Beverly Hills, 90210, which reportedly may have contributed to her experiencing memory loss and anxiety.

"I thought about it and there were two times that I could recall as major head-related accidents: the time Luke ran me over with a jet ski in the Pacific Ocean while filming a scene together, and the time a huge tripod-mounted light fell directly on my head and knocked me over on the set of 90210," she recalled the incidents. "Accidents happen on sets; there wasn't any wrongdoing. But still, maybe they'd had some effect on me."

At 24, Garth underwent a b----- augmentation and liposuction around her hips.

"I asked the surgeon to smooth me out, make me smaller," she wrote. "I wanted to disappear into the version of beauty that was being sold to all of us at the time: small, effortless, waif-like. And I thought if I could just carve myself into that image, maybe I'd finally feel like enough."

The Jennie Garth: A Little Bit Country star stressed that no one from the show pressured her into getting the surgery. Still, when she noticed the changes — which she described as an "illusion of acceptance" — she found the feeling addictive.

The book also explored her journey after being diagnosed with clinical depression when she was 18.

According to Garth, she "couldn't gauge how Shannen felt about being back on set" when the cancer-stricken actress returned to the show after leaving the original series at the end of its fourth season.

"It felt like she was a little removed and preoccupied during the filming, which now makes perfect sense. She invited me to her trailer for a glass of wine on a few occasions and we had some good hangs. But she didn't tell me the news that her cancer had returned," Garth wrote about her Beverly Hills, 90210 costar.

Out of all the cast members, Doherty only told Green about her cancer recurrence.

Garth expressed, "I wish I had known, but I didn't find out until well after we wrapped. I think I would have been able to support her in different ways as a friend and a coworker. That news was tough to hear — not only because of the weight of what she was facing, but because I realized I had been with her for weeks and never knew."