Beach Boys' Brian Wilson, Wife Melinda Say 'Love & Mercy' Biopic Was Tough to Watch

— -- Through the 1960s, Beach Boys founding member Brian Wilson dreamed up songs of pure pop bliss, such as “I Get Around,” songs that had buoyant melodies, inventive arrangements and heart-stopping harmonies. For millions of people, The Beach Boys songs defined the surf, sand and sun allure of Southern California.

Many say Wilson’s wondrous creativity peaked with the 1966 album, “Pet Sounds,” featuring timeless songs like “Wouldn’t It Be Nice” and “God Only Knows.”

“It was the greatest part of his life, great part of my life,” Brian Wilson said in an interview with ABC's Chris Connelly for “Nightline.”

But through all his great success, the brilliant, yet emotionally fragile, Wilson struggled with mental illness. His wife Melinda Wilson said over the years she learned about the toxic mix of voices in his head, the brutality of his father, and the drugs Brian used, all of which plunged him into emotional breakdowns and subsequent seclusion.

Living through all of this was one thing, but seeing the intimacy of their lives played out in front of them on the big screen in “Love & Mercy,” the biopic about their love story, was “a whole different ballgame,” Melinda Wilson told “Nightline.”

“I didn't know how tough it would be,” she said. “I think I was more nervous than him when I took him to see it, and after, I said, ‘So what did you think?’ And he goes, ‘Oh, it was really a lot worse in real life.’”

“Some of the things that I relived were sad, you know, sad and upsetting,” Brian Wilson said. “They were rough to watch.”

“Love & Mercy” uses two actors, John Cusack and Paul Dano, to chronicle two strikingly different times in Brian Wilson’s turbulent life.

“Anybody who was on this movie, you just look in each other's eyes, you'd be like, "OK, we're not here for anything else. Let's give this-- we're all in, right?’” Cusack said in an interview with “Nightline.” “This wasn't a money gig. This was, ‘OK, let's try to make a film and-- a real film.’”

Paul and I just sort of knew that we were going to not talk about it much and we hoped it would be two different impressions of Brian that would hopefully harmonize,” he continued.

By the mid-80s, Brian Wilson said he was under the abusive thumb of psychotherapist Dr. Eugene Landy 24-seven. Then a chance meeting with Melinda, who was then Melinda Ledbetter, shined a new light into his life.

“I remember meeting her at her dealership, Cadillac, and I said, ‘God, she's a pretty girl. That's a pretty girl,’” Wilson said. “I just said to myself, ‘God, I think I'll see her again sometime.’”

“That's what attracted me to him,” Melinda said. “He was so nice.”

In “Love and Mercy,” the multi-talented Elizabeth Banks, who most recently directed, produced and starred in “Pitch Perfect 2,” plays Melinda Wilson, and got a chance to meet her when Banks was preparing for the role.

“She said to me, ‘Music is his first love. Nothing can replace it. It's his being, it's his essence, it's his everything, So I'm settling for second, but it's a pretty good-- it's a pretty good second,’” Banks said of a conversation she had with Melinda.

“She fell in love with someone who was very damaged and had issues,” Banks continued. “I wanted to really try to understand where the purity of her love came from. They're perfectly mated and matched. And I felt that in talking to her and meeting her and understanding her… how she came to the relationship.”

Today, the Wilsons live in Beverly Hills with their five children. Brian will turn 73 this month.

“Love & Mercy” actors say they are proud to have a role in portraying his challenging times, and in celebrating his now acknowledged greatness.

“He's so vulnerable,” Cusack said. “But he's also a real survivor, if you think about the people who didn't survive the '60s or couldn't survive some of the things that he's gone through.”