“Listen, I am different,” the Grammy winner, whose 5-year-old son Noah is in remission from liver cancer after a devastating diagnosis two years ago, tells PEOPLE exclusively in its latest cover story. “You don’t go through big things in your life, dramatic things like I’ve gone through or my wife has gone through without it having an effect on you.”

Two years ago, just three minutes before he was set to perform in London, Bublé receiving a shocking text from his wife, Argentinean actress Luisana Lopilato, 31, that shocked him to his core: his firstborn son, then just 3 years old, was facing cancer.

Immediately putting their lives and careers on hold, the Vancouver-based couple moved to California and stayed by Noah’s bedside for the next seven months as he received life-saving care, including chemotherapy.

“Everyone understood in my world what my priority was,” says Bublé, 43, who is fiercely protective of his son’s privacy and declines to elaborate on the details of Noah’s treatment. “We all go through things. You just hope you learn something about yourself and you learn something about the people with you.”

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Both his and Lopilato’s extended families relocated to Los Angeles for support, and his loved ones “are who I thought they were,” he says. “Obviously everything can be super stressful, but I got some superheroes in my life.”

Now with all three of his children healthy and at home, the star, who is also dad to 2½-year-old son Elias and welcomed his daughter Vida in July, is facing life — and love — with a new outlook.

For much more on Michael Bublé’s new lease on life and how he and his family are healing, pick up the latest issue of PEOPLE, on newsstands Friday.

“I don’t think I feel very nervous for anything anymore,” he says about seeing the bigger picture. “The perspective that I have on life now allows me to understand that I don’t have to sweat the small stuff. I want there to be a purity, and I want there to be a focus on relationships and kindness. I’m spending my time doing things I love and with people I love, for people I love.”

Though he wasn’t always positive he would return to the recording studio, the star felt the best way to thank his fans for their support over the last two years was through music.

He teamed up with producer David Foster, and the pair focused on joy over pain through the recording process. “I said, ‘I don’t know if I’m gonna go back, but if I do, I just want it to be happy,'” recalls Bublé.

Emphasizing that he “never” fell out of love with music, Bublé insists he just “needed to put it aside” until he and his family were ready for him to get back into the spotlight.

“Coming back was really beautiful,” he says, adding that the positivity he received from strangers gave him a “real faith” in humanity. “I feel like every performance, every time I meet somebody on the street, it’s really an opportunity to look them in the eye and express my appreciation and how grateful we are for their love and their compassion.”

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Heading out on tour for the first time in three years in February, Bublé — who wrote the nostalgic track “Forever Now” off his new album Love for his kids — is purposefully scaling back the number of performances so he can continue focusing on his family.

“It’s important not to lose sight of what makes you most happy, and what makes me most happy is being with my kids,” he says. “I want them to have that steady kind of presence in their life.”

RELATED VIDEO: Michael Bublé Makes First Public Appearance Since Son’s Cancer Diagnosis: ‘I Stand Here Truly Humbled’

Before hitting the road, however, the entertainer will have a very packed house for the holidays — and that’s exactly the way he likes it.

“If you think I like Christmas, then double that by a zillion,” he says. “My favorite thing in the whole universe is just having my sisters and all their kids and my kids and blasting Christmas songs and dancing for hours. That’s happiness right there!”