Five months after losing her to cancer, Rory Feek is opening up about life without his wife, Joey Feek. On Sept. 4, Feek spoke with CBS Sunday Morning about his grieving process and how it's resulted in a documentary about his wife and their life together.

Joey + Rory performed together for almost 10 years, until Joey Feek's death on March 4, 2016.

"I don’t know if I expected it to be as heavy as it is, because we had so much time to prepare for it, but I think it’s that heavy when she’s that wonderful," Rory Feek tells CBS' Anthony Mason, adding that his wife's death still doesn't feel real. "It’s been, I don’t know, how long? Five months? And I’m still not quite ready. That’s the biggest thing I struggle with. I still walk around thinking, 'She’s really not here? She’s really not coming back?'"

Joey Feek was first diagnosed with cervical cancer just 13 weeks after delivering daughter Indiana in February of 2014. An initial surgery was believed to have removed the cancer, but it came back, and Feek passed away not long after Indiana's second birthday.

"She just believed God had a bigger plan," Rory Feek says about his wife's incomparable optimism and hope. "[She believed] that everything’s going to be okay, even if it’s not okay."

As he adjusts to life without his wife and raising Indiana as a single father, Feek says that he still has coffee with his wife every morning, sitting on a bench by her gravesite. Joey Feek was laid to rest on the 60-acre farm she shared with her husband, in a cemetery that began in the 1800s for the original owners.

"I just can’t bring myself, for some reason, to go and order a stone yet," Rory Feek says about the simple wooden cross marking his wife's grave. "I don’t know why, I just can’t. I don’t know if it’s that she’s so simple a wooden cross is part of what she would like. It probably has something to do with permanence.”

While the loss of his wife and the mother of his child was the biggest blow, Feek also lost his singing partner. The Feeks got their big break when they came in third on the CMT singing competition Can You Duet? Their success on the show led to their own television show, not to mention seven studio albums, a Grammy nomination and a win at the ACM Awards for Top New Vocal Duo of the Year. Their final album together, Hymns That Are Important to Us, landed at No. 1 on the Top Country Albums chart.

"No, I don’t want to be onstage without her," Feek says when asked if he's still writing music. "It wasn’t something that I loved that much, to be onstage performing. She loved to be onstage performing, and I loved to stand next to her. I just had the best seat in the house, to watch the world discover my wife."

One thing that Feek says has helped immensely is the work he's been doing on a documentary celebrating his wife and her impact on so many lives, including his own. To Joey, With Love will be released later this month, and it's been a major part of the mourning and healing process for Feek.

"This whole experience of making the film has been incredible because I get to see Joey every day," he says about the movie, which celebrates Joey Feek's life and their unique love story. "My wife stalked me! That’s what she says. She actually saw me play at a songwriter’s night in Nashville at the Bluebird Cafe. And that’s proof that there’s a God. Because there’s no way I could have landed that girl without His help!"

To Joey, With Love is set to premiere on Sept. 20, with a one-night-only screening at theaters in Nashville, Tenn.; Chicago, Ill.; Los Angeles, Calif., and more. An encore screening will take place on Oct. 6; fans can visit the film’s official website for more information. Rory Feek is also working on a book, titled This Life I Live and based on his blog of the same name.

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