"You're not tortured that long for nothing," Bertinelli told "Good Morning America" co-anchor Diane Sawyer today. "She was a very tortured soul. I'm seeing this light come out of her because she's letting go of a lot of that pain."
"It really kills me that people will not believe something coming out of her," she said. "I say give her grace."
Bertinelli let go of her own pain and found her own grace after losing more than 40 pounds on Jenny Craig and showing off her bikini body on the cover of People magazine. Part of that journey, she says, was learning to forgive herself.
"I'm still doing that everyday, daily…trying to forgive myself for who I believe I was," she said. "It's a daily struggle."
After sharing her personal strife and lessons in learning to overcome her addiction to food in the memoir "Losing It," Bertinelli is back with a new message and a new book: "Finding It."
This new book takes an intimate look at how she discovered how to live the best life possible at the age of 49. She offers advice on how to send yourself positive messages from "that little voice you hear in your head" to finding clarity in your life by cleaning out your closets.
"I do that often ... it helps," she said. "It takes away the chaos I think a little bit."
Bertinelli became America's sweetheart at the young age of 15 on "One Day At A Time," where she struggled with her own body image opposite co-star MacKenzie Phillips.
"If my jeans were two sizes bigger ... than Mackenzie's, I thought I was a fat hog," Bertinelli told "20/20" recently. "I just didn't think highly of myself. I always felt less-than."
Later, Bertinelli battled addiction to cocaine, a weakness she says she and former rocker husband Eddie Van Halen shared.
"Ed and I were playing with our vials of cocaine as we're filling out the forms the priest had given us to, you know, see if we're compatible for marriage," she told "GMA" in 2008.
Bertinelli and Van Halen's 20 year marriage, fraught with fighting and infidelity, ultimately ended in divorce. And just when Bertinelli thought her worries about a rock star's lifestyle were over, her son Wolfgang announced he was joining Van Halen and hitting the road with Dad.
That decision gave her "more than pause," she told Sawyer. She realized that if her teenage son was going to join the band, it was time for someone to have "the talk" with him.
"I'mm not real good at talking about the sex talk," she said. "A teenage boy doesn't want to hear it from his mother."
So Bertinelli turned to her former husband, although she had her doubts.
"Eddie Van Halen giving a sex talk?" she recalled thinking. "What am I, crazy?"
But she said Van Halen, who is a "terrific dad," did a great job, and advised his son to "be careful with your heart."
Bertinelli says her lifelong crutch -- through her divorce from Val Halen, to watching her son join the ranks of his dad's hard-partying band -- was always food.
"My weight gain was a symptom of where I was in my life and how unhappy I was," she said. "By taking off the weight I didn't all of a sudden become happy."