Michelle McCool Says It's 'Hard' to See Husband The Undertaker Get Injured But It's 'What You Do'

Mark Calaway is just doing what he loves — and both he and his wife, Michelle McCool, have accepted the risk, though it's not always easy.

Calaway — better known by his WWE in-ring name The Undertaker — and McCool, a fellow former WWE champion, are reflecting on his career in the latest issue of PEOPLE ahead of his 30th anniversary with the company this month.

During his three decades in the WWE, Calaway, 55, has been victorious in the ring, but has also faced scary injuries and grueling recoveries.

"It's hard," McCool, 40, tells PEOPLE. "For one, him walking with a limp, or him being injured, or any of us being injured for that matter, it kind of was your normal. I mean, you're in the ring 300 days a year, so your body's getting beat up."

Continues McCool, "And no injury is easy to watch, but then knowing it's your husband is a whole different story. That just adds a whole other level to it."

Even now, as Calaway's WWE appearances are rarer, it still can be "scary," McCool — who shares an 8-year-old daughter, Kaia, with her husband — says.

Check out more about the legacy of The Undertaker in this week's issue of PEOPLE.

"Just knowing one little mistake, or one little slip on some move, could just undo all the repair that they had done on his hips, or his knees, or his neck, or whatever the case may be," she explains. "Watching it is a whole lot scarier for me than me actually being in the ring myself."

Still, at the same time, the former WWE Diva says she loves watching Calaway perform.

"I know that my job as a wife is to kind of put my feelings aside sometimes, and just support whatever he wants, and then help him reach whatever goal that is. And we do that for each other," she tells PEOPLE, adding, "It's hard emotionally, it's hard physically, but that's what you do when you love somebody."

This weekend, Calaway will appear at Survivor Series — streaming on WWE Network at 7 p.m. EST on Sunday — for a special segment that the WWE is calling "Undertaker's Final Farewell."