His father, Joseph, was shot and killed on Thanksgiving Day when Cormier was just seven-years-old. Then, in 2003, his three-month-old daughter, Kaedyn, was killed in a car accident.
“I’m just trying to really honor the people that I’ve lost,” Cormier told CNN Sport’s Patrick Snell, ahead of his rematch with Stipe Miocic at UFC 241 in Anaheim this weekend when the 40-year-old American will defend his heavyweight title for the second time.
“I don’t let these horrifying things break me. I try to use everything as motivation to try to make a way for people, provide a life for my kids, my family, my wife, my parents.”
A two-time UFC belt holder, Cormier is currently ranked as the best pound-for-pound fighter in the sport.
He says the deaths of his father and daughter have been key to giving him a resilient perspective on life.
“There have been so many things I have been able to do for my family because I didn’t give up,” Cormier said. “I try to carry my entire family on my back. I try to be strong for everyone.
“Life can seem unfair but when it seems unfair, you’ve got to try and spin it in a way that allows you to use it as motivation. When you lose someone or go through the things that I’ve gone through professionally, it’s easy to say, ‘this isn’t fair’ and ‘I’m not going to do it anymore’ because when is life ever fair.
“All I can do is try to use it to propel me onto something bigger and better.”
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The best of rivalries
If the fight against Miocic is very much on Cormier’s mind, so too is his rivalry with Jon Jones, a fighter who inflicted the only UFC defeat on the 40-year-old almost five years ago.
In their rematch at UFC 214, Cormier was knocked out by his compatriot during a title defense, only to be reinstated as champion after Jones was suspended for testing positive for a banned substance before the fight.
But although speculation over a third bout between the pair has been rife since, the heartbreak of their previous fight means Cormier is hesitant to jump back into the ring with Jones.
“I haven’t decided if I want this rematch yet,” Cormier said. “He wants the fight because we make the most money when we fight but I haven’t decided if I want to help him out yet.
“It was horrible because after losing in the way that I did, it was time for me to move on and figure something else out. So, to bring that back was just horrifying.
“I was actually in Hawaii in vacation with my family and Dana White called me and told me about that and I was like ‘you gotta be kidding me?’
“It almost made me cry because I couldn’t believe I was going to be dragged back into that whirlwind of negativity.”
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A tougher opponent
Having beaten Miocic at UFC 226 to win the UFC Heavyweight Championship, Cormier successfully defended it against Derrick Lewis last time out.
A part-time fighter from Ohio who also works as a firefighter, Miocic hasn’t returned to the Octagon since that defeat, but Cormier expects a stiffer test when they face off yet again.
“I think this time Stipe will do a better job of trying to fight long, really stay at range instead of engaging me so close,” said Cormier.
“Last time he was the bigger guy, so he came in close with me a lot. I think this time, he will maybe fight backwards a little bit, try to fight off of his jab a little bit more.
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“He’s got a real long advantage in terms of reach over me, so he’ll try to use it in this fight.
“I know he will change a few things, but I do expect a better fighter in the Octagon on Saturday.”