In news that nobody needs reminding of, the teenage starlets went on to date for five years before breaking hearts across the globe by announcing their break-up in December 2010.
The following autumn, Hudgens was photographed holidaying with Butler - sending romance rumours swirling the Internet.
The couple has yet to confirm the breakup, but the last photograph Butler posted of the 31-year-old actress was back in July after they attended the Once Upon A Time In Hollywood premiere together.
Meanwhile, Hudgens last took to the social media platform to share a snap of her former boyfriend over Halloween 2019 with a photograph of the pair dressed in matchy-matchy The Nightmare Before Christmas costumes.
Tugging at fans' heartstrings even more, she used a rather apt quote from the film to caption the post.
"And sit together, now and forever. For it is plain, as anyone can see. We're simply meant to be," Hudgens wrote.
The High School Musical star last spoke about their relationship earlier this month, as she told Cosmopolitan UK: "It's eight years this year - FaceTime, good communication, respect and trust [are what keep us going]."
"The longest we've been apart was four months. It sucks! You start hating hearing yourself say 'I miss you.' But if it's your person, you make it work."