11/07/2016 05:08 EST | Updated 11/07/2016 06:17 EST

Bo Cooper, Fort McMurray Firefighter, Dies After Long Cancer Battle

He was an inspiration for many Canadians.

A Fort McMurray firefighter lost his fight with cancer Sunday, after a years-long battle against the disease.

Bo Cooper, known as Unbreakable Bo, inspired many Albertans with his courageous fight against acute lymphoblastic leukemia.

"This is the worst heartbreak I have ever felt," his wife, Irish, shared in a Facebook post Sunday morning. "My mind is not clear right now, it's like I'm walking in a fog of emptiness."

"He was holding on for so long, but he suffered too much. I miss him more than anything in this world, but he is no longer in pain."

Cooper, a former mixed martial arts fighter, was first diagnosed with cancer in 2011, and battled the disease into remission twice.

However, in the fall of 2015 he learned the cancer had returned.

Bo Cooper in his days as an MMA fighter. (Photo: Bo Cooper Leukemia Treatment Fund/Facebook)

Cooper, 27, was approved for experimental treatment last year, reports Global News.

The treatment was expensive, but, according to the Edmonton Journal, people from around the world helped his family raise more than the $880,000 needed to send him to the National Institutes of Health in Maryland.

By spring, it looked like the cancer was in remission. But by September Bo learned the treatment had failed.

"Even when he was down, he was always trying to help somebody else. And of course he was a firefighter that saved many lives," Wood Buffalo Coun. Keith McGrath told CBC News.

"I think his spirit is going to live on amongst his brothers and sisters in the firefighters association and he'll always be remembered."

"I miss him more than anything in this world, but he is no longer in pain."

People across the country shared their condolences on Facebook Monday.

"I have never met you and your family, but I followed along, and believed. These past two years of updates and stories you shared with us have been such an inspiration to thousands. You have set the bar high to all wives out there and have set an example for everyone else," wrote one woman on a page dedicated to sharing Cooper's battle.

"You'll always be a hero in my eyes and many other people. You're gone but not forgotten. You'll be missed by many," wrote another.

Like Us On Facebook

Follow Us On Twitter

Also on HuffPost

Photo gallery Fort McMurray Firefighters Battle Blaze (May 2016) See Gallery