"Some people don't survive, though, that experience phase," Cooper remarked.
"Yeah, I mean, I also don't think that it has to be so heavy. You know? It's like, 'Oh, it's just so tragic.' No, it wasn't," Barrymore said.
"It was an extraordinary experience. I went through it. And I learned a lot. And did I learn it in front of everyone, which was righteously embarrassing? Sure. But you know what? It made me stronger," she said.
It may have made her stronger, but at the time it wasn't clear she'd get through it. At the age of 13 she was forced into rehab, and ended up in treatment on and off for more than a year.
"When you were in rehab, you dad called you," Cooper said. "But he was calling to ask you for money."
"Yeah," Barrymore said. "Great dad. Yeah, he would ask me for money on birthdays and, you know, inappropriate times. And I just wrote him off like, 'You're not a father.' I just learned you cannot emotionally invest in people who are not attainable."
She had also learned that she could legally separate herself from her parents. She discovered that - from of all places - a movie she starred in. It was called "Irreconcilable Differences."
At 15, out of rehab, Barrymore petitioned the state of California to emancipate herself, arguing she would be better off without her mother and father. The court agreed, and she was on her own.
"I did what I had to do to get there, which was play by the rules and re-figure out my life and disconnect myself from the people I knew and the lifestyle I knew. And you know, prove that I was a responsible citizen with a good head on my shoulders. And I did. And therefore, I was rewarded by being emancipated," she explained.
Barrymore got her own apartment, signed her own lease, and got a job working at a coffee house called "The Living Room."
"And my boss just hated me," she remembered. "At one point he was like, 'Go live your dreams and get out of my shop.'"
Her agents told her she was overweight and unemployable, but she missed acting and missed the impromptu families that film sets create.
"I missed my tribe," Barrymore said. "And I was really alone out there. And so I just started going on auditions again."
It took her years of TV movies and small roles in low-budget films, but Barrymore won Hollywood and audiences back. Her quirky sense of humor and "girl next door" appeal have made her a leading lady in a number of hugely successful romantic comedies.
"People seem to root for her no matter what the film is, no matter what role she's in or what she's doing," Cooper told Steven Spielberg.
"Well, you know, it's very easy to root for the little girl in E.T. And that little girl has grown up. But she's still the same character that she was in E.T. You know, she just has a kind of - she casts a spell," Spielberg replied.