I first met Mariel Hemingway on Twitter, and then in her one-story home nestled deep in the Santa Monica Mountains.

It was there that she talked about her first encounter with Woody Allen, but also about the legacy of Ernest Hemingway, and how she tried to learn everything about him growing up. I didn’t realize at the time how deeply she was affected by the grandfather she’d never met.

But what became evident in our “Media Buzz” interview, airing Sunday, is that her adult life has been shaped by growing up in a family plagued by mental illness. That included seven suicides, including those of the world-famous author and Mariel’s actress sister, Margaux.

“I can’t deny that when Margaux committed suicide, which was an incredible surprise, like oh my God, the baton has been passed to me, who else does it go to but me?” she told me. Hemingway said that most of what she’s done since then—her immersion in nutrition and fitness and promoting a healthy lifestyle—are in reaction to her upbringing (including her alcoholic parents). She also talked about her reasons for reliving her painful past, as she does in the documentary “Running From Crazy,” debuting Sunday night on the OWN channel.

I’ve always been fascinated by people who have to cope with fame from an early age, and what that does to them.

Growing up with that famous last name, becoming a teenage movie star, have put Hemingway in the glare of the media spotlight for decades. But she says she tries to keep out of the gossip columns: “I have to be honest, Im not the best celebrity…I’m just failing, I don’t go to events.” She is, instead, a “private person.”

Hemingway recalls her first real kiss, at 16: It was in front of the cameras, with Woody Allen. So I had to ask her about the revival of child molestation allegations against the famed director by Mia Farrow and the New York Times. You’ll see how she handles that, as well as a question of whether Hollywood has room for aging actresses.

Given all she’s been through, I’m happy to report that Mariel Hemingway is decidedly not crazy, or at least no crazier than the rest of us.

Watch the sneak peek above and tune in for the full the interview on Media Buzz, Sunday at 11a/5p ET.