We’re getting closer and closer to finally seeing the buzzed-about Kurt Cobain documentary, Montage of Heck. It’s scheduled to land in U.S. theaters later this month, and then it will make its TV debut on HBO on May 4. Ahead of its release to the wider public, director Brett Morgen has revealed yet another intimate detail extracted from Cobain’s archives, specifically what Morgen calls the late Nirvana frontman’s “actual suicide letter.”

“I found his actual suicide letter, which was unexpected,” Morgen told NME. “I just opened up this heart-shaped box and there it was. And I was like, ‘Based on everything I’ve witnessed, this makes no sense.’”

“Kurt didn’t have a problem with quitting music; he talked about it openly,” the director continued. “If he wanted to stop performing, he would just stop. Nothing was leading up to that suicide letter.”

Instead, Morgen suggests Cobain’s death had more to do with his family than his career.

“It was ultimately about his search for family,” Morgen explained. “He didn’t feel like he had a family, but he desperately wanted one. So the second that Nirvana broke he asked Courtney [Love] to have a child. You’re 25 years old, you’re the biggest rock star in the world -- having a baby isn’t a very common reaction, you know?”

In a Montage of Heck interview, Love reveals that Cobain attempted suicide almost exactly one month prior to his death in 1994, and she says it was because he believed she was considering cheating on him. Morgen agrees that this theory played a role in his suicide a month later, saying the singer “died of a broken heart.”

“He thought his wife cheated on him, and [she] and Frances were all he had,” Morgen said. “The film invests a lot in trying to understand why Kurt would react the way he did to betrayal. We try to find the square root of it.”

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