The story of a comeback attempt by a former wrestling golden boy fallen on hard times, "The Wrestler" parallels Rourke's own return to the sort of critical acclaim he once earned with such films as "Diner," "Rumble Fish" and "Barfly."
"I ruined that myself," Rourke said in an interview with The Associated Press at the Toronto International Film Festival, where "The Wrestler" screened. "I wasn't ready at that time. There were some broken pieces I didn't know how to fix that made me behave a certain way. I wasn't knowledgeable enough for many, many years to understand or want to accept the fact that the movie business was political, and that it's a business. You know, coming out of the Actors Studio, I thought it was just about acting, and I knew I could do that. And I knew I could do that better than most people.
"That's what I carried around, and I was very wrong. Very wrong, very immature, very uninformed, very uneducated about that. I wish I knew differently, because I put myself and a lot of other people through a lot of hell that I regret."
In 1994, Rourke was accused of spousal abuse against his wife at the time, actress Carre Otis. Charges later were dropped after prosecutors were unable to get Otis to testify.
An amateur boxer in the 1970s, Rourke went pro in the early 1990s, a time when his movie career had dried up.
In the years since, Rourke has had occasional success in supporting roles, notably his turn as a colossus of a man on a vengeful rampage in "Sin City."
"The Wrestler" marks the first time in ages anyone has entrusted Rourke with a lead role, let alone a challenging, sympathetic one. Director Darren Aronofsky fought to cast Rourke, whom potential financial backers did not want in the film.
Aronofsky only got his way by paring the film down to a $6 million budget, small change by Hollywood standards.
The payoff already has been big. "The Wrestler" won top honors at the Venice Film Festival last weekend and was picked up for U.S. distribution at Toronto this week by Fox Searchlight, which plans to release it in December, the heart of Academy Awards season.
Rourke, who turns 52 on Sept. 16, is getting solid Oscar buzz for "The Wrestler."
"There's an incredibly honest performance in the film, and the fact that people are reacting is not surprising to me," said Aronofsky, whose previous films include "Pi" and "Requiem for a Dream." "We all knew how great and talented he was. He just hasn't had the opportunity to show the world for a while.
"I'm just honored literally to be the guy who was lucky enough to get Mickey at the place and time in his life when he was ready to open up once again to the world."
"The Wrestler" stars Rourke as Randy "The Ram" Robinson, a giant in the ring who played Madison Square Garden 20 years earlier but now scrabbles by on matches in high school gyms and community centers. A rematch of his most-famous bout offers a chance to reclaim former glory.
Meantime, he makes fumbling efforts to patch things up with his estranged daughter (Evan Rachel Wood) and romance a reluctant stripper (Marisa Tomei) while trying to keep his deteriorating body in form with steroids and tanning salons.
Doing twice-a-day weightlifting sessions and eating six meals daily for six months, Rourke packed on 40 pounds of muscle for the role.
His mental regimen has been a marathon by comparison: 13 years seeing a therapist, which he had resisted for a long time.
"I didn't think anything was wrong with me. I thought it was everybody else," Rourke said. "And there was a lot wrong with me, but it had to do with old stuff from my childhood that I had a lot of shame about. I'm a very proud man. Because I didn't want to feel shame, it was easier to manifest that into anger and a hardness, and then it eventually got too hard, and I realized that when I lost everything.
"I mean, everything. Not just my movie career. Then you're alone," said Rourke, adding that he remains in therapy. "I still have to work on it every day, because the little guy with the hatchet still lives inside of me, and he's sleeping now. I don't want him to ever wake up again."