The former couple were crowned the champions of last year's dating show and took home the £50,000 cash prize together.
Just five weeks after, Greg allegedly dumped the Geordie babe by text amid claims the pair struggled to make things work due to long-distance.
The reality star reportedly felt "used" by the Irish rugby star at the time of their break-up.
Amber took to Twitter earlier this week to mark a whole year since the couple became Love Island winners, but claimed it was all down to herself - hinting she's still not over how things ended sourly.
She wrote: "Can you believe it's been one whole year since I won Love Island."
While Greg, who Amber made no mention of, snapped back: "Congrats."
Greg's fans were in shock at the sassy response, with some agreeing with him.
One wrote: "Should have kept the 50k lad."
A second shared: "Yes Greg, such a legend."
As a third added: "Doing it for Ireland. Guwann Greg."
While others had Amber's back, with one writing: "Why is Greg talking???"
Another sarcastically penned: "How lovely of you to wish the first solo winner of Love Island congrats on her one year anniversary."
One fan was furious at Amber for not mentioning Greg, who contributed to her infamous win.
They wrote: "Since yourself "and Greg" won is what you meant to tweet. Don't underestimate the fact that Greg had lots of fans also. Ye may not be together but that's no reason to ignore his contribution to the votes."
The former couple couldn't make things work after leaving the villa as Amber lives in Newcastle and Greg in Ireland.
Greg was reportedly aware of the distance and had told Amber he'd visit often, but it didn't appear to be the case.
A source told The Sun at the time: "Amber feels used by Greg. He was always aware of the distance and his career in their relationship, and yet he chose to seek out Amber in the villa knowing there would always be the distance.
"He hasn't made any effort to come to London to see Amber, despite it being over five weeks, it's always Amber who had to make the effort."
Greg responded to Amber's claims a few months later.
On Irish chat show The Late Late Show, he said: "So we're mad about each other, what's not to be mad about? She's gorgeous, smart funny, she's the Queen of Love Island for a reason but you need to be realistic about the situation.
"She lives in the UK, every brand wants to work with her, every event wants her there, of course she deserves all of it and I decided to come back to Ireland and do my thing here.
"I'm trying to get to the Olympics with the sevens team, I've got my law exams coming up so we're both so jam-packed busy and you need to take these opportunities by the scruff of the neck.
"So we're kind of just being realistic about the situation and protecting our careers and that's where we are at the moment."
Meanwhile, Greg has moved on with law-graduate-turned-athlete girlfriend Emma Canning, and Amber is living her best single life.