Travis Kelce and Taylor Swift are “so in love” (Exclusive Source)

The turbulent summer of Travis Kelce and Taylor Swift is coming to an end.

As Kelce, 34, returns to Missouri for training camp with the Kansas City Chiefs after a summer of work and travel with Swift, also 34, a source told PEOPLE exclusively that the tight end wanted to spend every moment with his superstar girlfriend before returning his focus to football.

“Travis’ last concerts were bittersweet,” the insider says of Kelce’s trip to see Swift in Germany as part of the Eras Tour.

“They knew their time together was coming to an end, and he made sure to spend every possible minute with Taylor,” the insider adds.

Swift and Kelce’s busy schedules often force them to be in different cities, but the source says the “Fortnight” singer and the NFL star take every opportunity to spend time together, as their relationship is now nearly a year old.

“It’s definitely hard being apart, but they’re doing everything they can to make it work and be there for each other,” the source says. “They’re so in love and very, very happy together. All of their friends and family can see that.”

Kelce – who also spent his offseason shooting Are you smarter than a celebrity? and Ryan Murphy’s upcoming series grotesque – “is back in football mode,” adds another insider. “His team and the Chiefs remain his top priority.”

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The Chiefs will hold their open practices during training camp at Missouri Western State University in St. Joseph. They will play their first preseason game against the Jacksonville Jaguars on August 15 before the regular season begins on September 5.

When Kelce and his teammates returned to training camp on July 21, the tight end sported a fresh new look to start the season. In a Chiefs post on Instagram, the team highlighted Kelce’s new mustache look, writing, “KILLA STACHE IS BACK 👨🏻.”

Swift will perform in Hamburg and Munich this week before moving on to Poland. She will then return to the US in October to complete her record-breaking Eras tour.