Decades have passed since Vince Gill and Amy Grant endured what she calls “those long years” — the time between their first meeting in 1993 and when they became a couple in 1999 — but Grant says thinking about them still “makes me sweat.”

The reason is obvious: From the start, the chemistry between the two artists was undeniable — not only to each other but also to anyone around them — and yet both were in their first marriages at the time.

“It was not anything that we orchestrated,” Grant, 64, tells PEOPLE in a joint interview with the couple, who recently released their holiday album When I Think of Christmas ahead of their annual Christmas residency at Nashville’s Ryman Auditorium. “It was like life orchestrated that we kept crossing paths.”

Thankfully, the stresses of that era are ancient history for Grant and Gill, now happily married almost a quarter-century. Still, they continue to glean a wisdom and perspective from their journey that could inspire anyone seeking second chances.

“Life is full of all kinds of mysteries,” says Grant. “And I’m not saying any of us did it all wrong or all right, but what we’ve experienced is just so much grace and forgiveness for each other and for our first families and our second families, and it is possible to reconcile. It’s possible to mend fences. It might not be in the context of original relationships, but it’s possible to find your way in life with respect.”

The two first met when Gill, already a major country star, invited Grant, herself a hit-making trailblazer in Christian pop music, to appear as a guest on his Christmas TV special.

“I just remember the smile,” Gill, 67, says. “That’s all I can remember. It was a staggering smile that just stopped me in my tracks. And that had never happened to me before like that.”

Grant recalls being nervous before rehearsal, and her first memory of Gill was his act of kindness: “I just walked into the rehearsal space and Vince came over and put his arm around me and said, ‘Hey, unknit that brow, it’s going to be okay.’ I remember saying, ‘Wow, thank you for saying that.’”

Musically, they clicked, and after the show’s taping, professional get-togethers seemed natural. Gill returned Grant’s favor and made a guest appearance at her Nashville holiday show that year.

Soon afterward, Gill famously felt a stroke of inspiration from what had first captivated him about Grant: “I was writing songs with a buddy of mine, and he said, ‘What do you want to write about today?’ I said, ‘Let’s write a song about Amy Grant’s smile.’ He said, ‘Do you even know her?’ I said, ‘Not very well, but she’s sure got a great smile.’”

The romantic ballad he and Pete Wasner wrote, “Whenever You Come Around,” eventually became one of Gill’s biggest hits, as well as a signature song. Before its release, Gill shared it with Grant during a songwriting session of their own, and she recalls, “All I could think of was, ‘Goll, lucky girl.’” It would be years before she learned that she was Gill’s muse.

Grant also invited Gill to duet with her on “House of Love,” the title song on her 1994 album. Though Grant had no hand in writing the lyrics, they now seem uncannily prescient: “Sometimes life is funny / You think you’re in your darkest hour / When the lights are coming on in the house of love.”

In fact, both their marriages were by then rocky. Grant had wed Christian artist Gary Chapman in 1982, and they had three young children, a son and two daughters. Gill wed country artist Janis Oliver in 1980, and they had a daughter. Grant and Gill’s chemistry didn’t go unnoticed by their respective spouses.

“I think the energy was palpable to all of us,” says Grant, “and we tried to be so respectful. You can’t unknow. You can’t unsee something. And years later, I have said to Janis, ‘You could have been all kinds of ways, and you were so kind to me.’ That was a hard stretch.”

Says Gill: “What was painful was most people assumed the worst of us, and it was not fair, and it was incorrect. You couldn’t go back and undo what people said, and what people thought … Sadly, it’s human nature in a way to assume the worst. It couldn’t have been further from the truth.”

Gill and Oliver eventually divorced in 1997. Grant well remembers Chapman learning about it in the newspaper: “Gary laid it down — that’s the first any of us heard about it — and he went, ‘Oh dear God, somebody finally made it to the wall,’ because it was hard on everybody.”

Grant and Chapman undertook marriage counseling, but they announced they were separating in December 1998, and their divorce was finalized the following June. Four months later, Grant confirmed in an interview that she and Gill were dating.

Finally, Gill says, they had arrived at a moment when “the most beautiful truth” of their connection “was allowed to find itself.”

The couple married in March 2000, surrounded by friends and family — “the people,” says Gill, “that really, for me, encapsulated my whole life. Just face after face after face after face were all people that were rooting for you, cared about you.”

Quickly, the challenging work of blending families began. But a year later, the birth of their daughter, Corrina, came with a bonus, helping the couple overcome many of the hurdles of stepparenting.

“It connected all of us in a way, in a blood way, that was beautiful,” says Gill.

Both Grant and Gill say they’ve benefited from the life stage they were in when they wed. “One thing about marrying at 40 and 43,” says Grant, “is you don’t ever presume. I go, ‘You’ve lived a whole life, as have I.’ You walk into everything [saying], ‘Hey, this is sort of how I’ve done this. How have you done that?’ It’d be great if people did that at 21, but it’s an easier lesson in your forties.”

Gill adds: “We just gave each other the grace to be what we’ve always been and then just kind of let it unfold from that … Sometimes we kind of cannot see eye to eye on how things should go, [but] I’d rather be kind than be right, and I think she would be, too, because that’s what she has going for her. It is a common kindness that I’ve never seen.”

The two also have found other ways to navigate their differences. Grant, for example, is an adventurer who loves to travel. Gill is a homebody who gravitates to the music studio or golf course. They make it work, says Grant, because “one thing that we’ve given each other in our marriage is freedom,” all while knowing that “you’re the person I want to return to.”

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Just three months shy of their 25th wedding anniversary, the couple are now savoring what Grant calls “golden years” — a time that “feels magical.” Their lives are filled with friends and family, children and grandchildren, and the satisfaction of career accomplishments that still keep coming. But, says Grant, they derive a bounty of their joy simply from their togetherness, often in simple, quiet evenings at their Nashville home.

Grant says Gill loves to tease her: “He’ll say all the time, ‘Would you marry me now?’”

Grant doesn’t even ponder the question. “Yeah,” she says, and the answer comes out almost like a sigh. But what really says it all is the smile.