Guns 'N' Roses' Duff McKagan and Wife Susan Holmes Reveal the Secret to Their 22-Year Marriage

Susan McKagan Duff McKagan and wife Susan Holmes McKagan

Duff McKagan and wife Susan Holmes McKagan's relationship is like a trip to "Paradise City."

In an interview with PEOPLE, the Guns 'N' Roses bassist and the Velvet Rose author reveal the secrets to their long-lasting marriage, even when Duff is on tour with the rock band.

"You can't have a bad day with her. If you're having a difficult day, she'll make it better," says Duff, 57. "And I love everything about her. We have an amazing love life and we got each other's back. We're ride or die, as they say these days."

Adds Susan, 49, "It's a balance. Just knowing and respecting each other's careers. It's a dance. We just genuinely enjoy each other's company a lot. We have a lot of fun."

"And now, since COVID, Netflix and chill. We're into that," chimes in Duff with a laugh, before adding, "We keep it romantic. In our marriage, there's still some mystique. She's still mysterious to me."

Duff and Susan — who reside in Seattle — got married in 1999 after meeting on a blind date four years prior ("It was fate," says Duff). They share daughters Grace, 24, and Mae, 21.

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"Duff is the most amazing, wholeheartedly wonderful husband and father. He's a girl dad. He's such a good girl dad," she says.

Though their daughters are older now, they continue to have that love for young children. After the interview, Duff shared that they'd be babysitting for a friend's 6-year-old daughter.

"We're going to make pumpkin cookies and pizza and we're going to watch some new Muppets Haunted Mansion movie together. We're excited," says Susan.

"She's the best mom there is," adds Duff. "She's just a natural."

As for when they spend time with Mae and Grace, Susan says they like having tea together and going to rock shows, especially LCD Soundsystem, which is their "family band." Last week, the couple went to Disneyland with daughter Grace.

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"They're not embarrassed by us as much," says Susan. "We're just very close and I'm just so proud of our girls."

Mae is a full-time student (with "amazing grades," adds Susan) and a part-time model. Meanwhile, Grace recently released her single "One You Love." She's also working to become a CorePower Yoga instructor. ("She's in intense yoga training right now," says Duff. "I think she has to complete 500 hours.")

"The girls really look up Susan. And I think because we're a married couple in love, they see that. I'm sure they've seen us work out stuff through the times of them growing up they see, like 'Ok, this is like a solid relationship.' And I think they aspire that," adds Duff.

When asked what keeps the spark alive between Susan and Duff, the bassist answers immediately. "I just can't get enough of her," he says. "I pinch myself. I'm super fortunate. You can never have a s—ty time with her."

When Duff is at home, the couple loves going on date nights together. Since they live by a lake, they'll sometimes boat to dinner or watch a good classic movie at home.

And when he's on the road with the Axl Rose-fronted band, Susan makes sure to not go two weeks without seeing her husband.

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"I make sure we go to the coolest, maybe not-so-obvious, crazy things to see and do," says Susan. "We went to the torture museum in Amsterdam. Like who goes to that or knows about that? That was kind of a kinky, fun date."

"Nothing wrong with that either," adds Duff with a wink.

As for what the couple has learned after being together for so long, Susan says it's that "true love is unconditional."

"He just genuinely loves me for who I am. He loves me when I wake up and have bad breath, just, the not glamorous Sue. We're very old-fashioned in a lot of respects, I guess," she says.

Adds Duff, "There was something when we met, there was a deeper thing and I knew I was going to love her. I knew it. And then four weeks went by, I'm like, 'I'm completely overwhelmingly in love.' I'm not a hippie woo-woo person, but there was something old soul about us meeting. I felt something timeless about us when we met. Timeless is the word."

Now that they've been empty-nesting, the couple is getting a good amount of alone time.

"Now that they're out of the house, we're having more fun. And we mean that in the nicest way," says Susan. "I mean like sexy time fun."

"Oh you said it out loud!" adds Duff with a laugh.