Robert Gropel, who climbed Mount Everest with his wife Maria Strydom in an attempt "to prove that vegans can do anything," has spoken out for the first time about her death. And he says he blames himself for the tragedy.

Speaking with Australia'sSunday Night, Gropel describes Strydom falling ill once they got near the summit.

"I asked, 'Do you mind if I go on,' and she said, 'Yes, you go on, I'll wait for you here'," he said on the show. "She was feeling strong, she was walking, I mean she was short-roped because she was still quite weak, but she was walking fine, very slowly but fine. She was talking, I had her back and I don't know what happened."

The couple, who make the trek "to prove that vegans can do anything and more" spent a year preparing. But Gropel, who was also suffering from altitude sickness, ended up making it to the top alone.

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Robert Gropel

"When I made it to the summit of Everest it wasn't special for me because I didn't have her there," said Gropel, who is also a vegan. "I just ran up and down and it didn't mean anything to me."

The couple and the rest of their group spent double the amount of time recommended at the top, the most dangerous part of the mountain dubbed the Death Zone. Gropel says it took them longer because they ran out of oxygen.

"Maria and I spent 30 hours above Camp Four," said Gorpel, who climbed the six of the other highest peaks in the world with his wife. "I don't know anyone who's suffered what she suffered at the altitude that she was at and could have done what she did."

On the way down, Strydom began hallucinating and speaking gibberish. She collapsed just before getting to the final camp, according to reports. It's believed she was affected by fluid built up in her brain from altitude sickness. Gropel had to be brought down the mountain by sled and was taken to a hospital in Nepal.

He says he's too heartbroken to look at photos of his wife.

He told the outlet: "Because I am her husband, it's my job, it's my job to protect my wife and get her home. It's just natural for me to blame myself."

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