But the pair were separated when Seaborn left high school to attend Duke University in Durham, North Carolina.
Sheeran did not begin dating the consultant - a keen hockey player who competed in British University Championships - until 2015, when she was working on Wall Street, the financial district of New York.
To combat the long-distance, the pair spent most of 2016 travelling the world together as Sheeran took a year off from the music business.
In December that year, Seaborn transferred to the London office so that she could move in with Sheeran and the pair have been blissfully happy since.
Speaking last year, the Perfect hitmaker revealed there was potential for their relationship to become a "marriage thing", as he reasoned: "I'm pretty... yeah I feel pretty good about it."
Sheeran went on to confess he'd "love" to start a family with his old school pal.
Of their sweet yet simple life together, he told Clash magazine: "I always thought to have a really good career, you always had to be incredibly unhappy, and I always thought to be really happy, you had to have a bad career, because I didn't see the balance of the two.
"And I've realised that that's obviously bulls**t, and just what you tell yourself to justify it.
"I live with Cherry now. We've got cats, we have takeaways and watch movies, we have people round for dinner. I've never had that."
The Grammy winning-artist revealed last year that he'd finally had the chance to fall in love after taking a break from music.
"This has been the first time I've ever actually had the time to fall in love properly," he told Zane Lowe on Beats 1. "I've always got into relationships very passionately - I'm a redhead and also Irish."
The end of 2017 was a cause of celebration for Sheeran, not just with his engagement, as he managed to scoop the UK Christmas number 1 with his song Perfect, featuring Beyonce.
Sheeran revealed it was an "actual dream come true" and he was "very proud" to reach the top spot with Perfect - that was inspired by Cherry.
