Rory Feek Celebrates First Mother's Day Without Joey: 'Thank You for the Beautiful Gift My Love'

"This is not my day. It is hers."

Rory Feek honored his beloved late wife, Joey Feek, with a heartbreaking message on Mother's Day.

The 51-year-old country-bluegrass singer took to his website, This Life I Live, to talk about life as a single father again after Rory died in March following a battle with cervical and colorectal cancer. Before meeting Joey, Rory was already a father to his daughters Heidi, 29, and Hopie, 27. Rory and Joey welcomed their 2-year-old daughter, Indiana, in February 2014.

Rory admits he wasn't always the best dad he could be to his eldest daughters.

WATCH: Joey and Rory Feek -- Remembering The Sweetest Moments Together From Their Final Year Together

"I can't tell you I was a great father. I tried," he candidly writes. "I think was a good father, but the truth is I was still a young man struggling to find myself, while the girls were growing and finding out who they were. I made so many mistakes and was so selfish. At times I was more concerned about being a great songwriter than being a great father. In a lot of ways, I think the girls raised me while I was raising them."

Rory says he dreamed about getting a second chance at being a father, which came true when Joey became pregnant with Indiana. Of course, the couple were then devastated as Joey's cancer progressed.

"Last fall, when Joey and I found out that the treatments weren't working and that more-than-likely, she wasn’t going to live to see another Spring… Joey sat beside me on a glider on our back deck and cried and cried," he recalls. "But not because of the news that the cancer had spread and there was nothing more the doctors could do. She cried because Indy was going to lose her mama, and I was going to be a single father again."

Still, Rory saw a bigger plan.

"I realized then that God knew what was in store and all those years by myself with the girls was him preparing me for the job of caring for Indiana," he writes. "We never cried over that again. We just celebrated every day that we were given together, and tried our best to prepare for the day when those days together would be no more."

The Feek family is definitely thinking of Joey on the bittersweet holiday.

"Though my beautiful wife sleeps in a bed of clover behind our farmhouse, we still celebrate her on this special day and lift her up and give her flowers. This is not my day. It is hers," Rory explains. "Joey loved being a mother more than anything else in the world. And she is still Indy's mama. And Heidi's and Hopie's. And she is part of them."

"And I still see Joey beside her," he writes about Indiana. "With us. Everywhere we go. And all the pain and fear that I feel melts away… and it's replaced by the feeling of how lucky I am…that we are. Indy's so beautiful.. When I look into her little eyes… all I see is love ... and the incredible second chance I've been given to be a father.

"Thank you for the beautiful gift my love," he concludes. "Happy Mother’s Day Joey."

WATCH: Rory Feek Grants His Late Wife Joey's Wish for Daughter Indiana

Last month, Rory shared a photo of Joey's gravesite at their family farm in Tennessee. Joey was 40 years old.

"A bright sunrise will contradict the heavy fog that weighs you down," he captioned the somber pic on Instagram.

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