In an emotional message to supporters, Lindsey Cappotelli said her late husband was the person she "wanted to grow old with" but she knows "where he is now is so much better".
She wrote: "Today, my love - my strong, sweet, beautiful love - took his last breath at 3:30am and went home to be with Jesus - exactly one year after his brain surgery."
"I miss him so much. I know where he is now is so much better, but it doesn't change how much I miss him."
Matt, who appeared on the WWE Superstars show and won the third season of the WWE Tough Enough series, was diagnosed with a glioblastoma brain tumour after complaining of headaches and seizure-like symptoms last June.
The late professional wrestler, who was previously a member of the Western Michigan University football team, had previously needed cancer surgery eleven years ago.
Speaking to WWE.com at time - in April 2007 - he said: "God is in control, and I have complete faith in what he's doing.
"There's a scripture I read quite often that describes my situation; it says God's strength is made perfect in my weakness, and I think this is a time where I'm at the darkest point of my life."
A surgeon was able to removed 90 per cent of the glioblastoma when he underwent surgery on June 29th 2017.
WWE is saddened to learn that Matt Cappotelli, a promising Superstar who was a co-winner of WWE Tough Enough III, passed away Friday at age 38. https://t.co/MCuoAHBkt6
— WWE (@WWE) June 30, 2018
Lindsey went on to say: "So many times I've wished that it were me going through this.
"I would trade places with him in an instant.
"I can't believe this is really happening. But it is. And this is part of life. People get cancer and people die.
"We can't do anything about that, but we can control how we respond to these circumstances and how we allow God to work in us and through us.
"I can already see the growth and change in me."
"It sucks to go through something like this, but I know God is working and moving.
"All the both of us want is for Him to be glorified. As Jesus said in John 12: 28, Father, bring glory to Your name."
In a statement, WWE added: "WWE is saddened to learn that Matt Cappotelli, a promising Superstar who was a co-winner of WWE Tough Enough III, passed away Friday at age 38.
"WWE extends its condolences to Matt Cappotelli's family, friends and fans."
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