Why Taylor Swift and Travis Kelce’s ‘serious’ relationship ‘feels different’

Taylor Swift may do that with a broken heart – but with her boyfriend Travis Kelce by her side, she doesn’t have to.

After their most public display of love yet, the pop superstar and her Kansas City Chiefs star boyfriend are heading into the summer stronger than ever, a source close to the couple tells PEOPLE in this week’s cover story.

“They are really, really happy together,” says the insider. “They are very serious about each other and the relationship feels different for both of them.”

Fans got to see her playful side first hand on June 23, when Kelce carried Swift, 34, onstage during an introduction to her song “I Can Do It With a Broken Heart” from her latest record-breaking album. The “Tortured Poets” section.

During the segment, 34-year-old Kelce powdered Swift’s face and showed off a few dance moves alongside her dancers while dressed in a top hat and tuxedo.

“They have so much fun together and it just works,” the source says of the couple. “Their friends find it funny because at first everyone was wondering what they had in common, but then you realize how similar they are. They both wear their hearts on their sleeves and are full-throttle in everything they do, whether it’s careers, family or friends.”

Swift’s focus remains on her Eras Tour, which recently spent three nights at the Aviva Stadium in Dublin, Ireland. (Fresh off the plane from LA, Kelce entered the stadium in the middle of the final show and was seen chatting with Julia Roberts in the VIP tent.)

Swift is next scheduled to play three shows in Amsterdam starting July 4 and will remain on tour until December, when she will end her record-breaking tour after more than 150 shows.

“This feels so far away, but then again, it feels like we’ve just played our first show on this tour because you made it so entertaining for us,” she told the audience in Liverpool on June 13. “It’s taken over everything. I think I used to have hobbies, but I can’t remember what they were because when I’m not on stage, I’m just sitting at home trying to think of clever acoustic song mashups.”

Kelce, meanwhile, will report to the Chiefs’ training camp on July 21. The team’s first game of the 2024 NFL season will be on September 5 against the Baltimore Ravens.

“Football is definitely still his priority, but so is his relationship,” the source says. “He makes romantic gestures to show he’s thinking of her when they’re apart. She will try to attend as many games as possible.”

Meanwhile, a second insider said Kelce was “thrilled” to accompany his Grammy-winning girlfriend to London.

“They loved being on stage together,” the source says. “He’s confident and funny, and it was one of their tour highlights.”

The “Karma” singer and the tight end were first linked in September when Swift made a public appearance at a Kansas City Chiefs game. Since then, they’ve taken their romance internationally, traveling to Australia, Singapore, Italy and more.

In an episode of Kissing with the boys In the podcast recorded on June 19, Kelce spoke more openly about their relationship than ever before and revealed how Swift has seamlessly fit into his life despite his sometimes chaotic football career.

“She understands these situations, and I think that’s why I really fell in love with her, because she’s so honest with friends and family,” he said. “So much attention can drive you crazy, but she’s so laid back and cool. … She wants to be a part of it. She wants to support me.”

For more on Taylor Swift and Travis Kelce, pick up the latest issue of PEOPLE, on newsstands this week.