In an interview with Ladies Home Journal, the Today Show host revealed that the illness has forced them to change their active lifestyle and restricts them from doing as much as they used to.
"I feel cheated sometimes," she said.
"We used to run together and go on ski trips or go to the beach. Now, it's very hard for Richard to stand. But we're very lucky in what we do have."
Vieira went on to say that Cohen's multiple health issues have forced the couple to maintain a positive sense of humour.
"We've had plenty of [hard times], partly because of health issues, which put a strain on the relationship," she explained.
"And we're both stubborn people - we can lock horns easily. But a sense of humour helps."
She added: "If something were to happen to Richard, I would never get married again. It's hard work to be married. I've been married once - that's the guy."