The pair both attended the same Hyper Karting event in Moore Park on Thursday, with Harrison having no idea Abby was there until she suddenly sat behind him.
An onlooker tells Yahoo Lifestyle Harrison and Abby spent the night awkwardly avoiding each other, despite being just metres apart.
“Harrison had absolutely nothing to say to Abby and did his best to try and avoid her,” they told us. “He's happy with his new girlfriend Gina and doesn't care for the drama.”
The reality TV star-studded event was attended by a number of season 10 cast members, including Joshua White and rumoured couple Evelyn Ellis and Duncan James.
Season nine brides Olivia Frazer and Carolina Santos were also in attendance, as well as former participants Melissa Lucarelli, Dean Wells and Nasser Sultan.
Harrison and Abby's relationship bombshell
Harrison’s on-screen 'wife' Bronte Schofield was left stunned on their wedding day when she was told he had a woman waiting for him in the outside world - who was later identified as Abby.
One of Bronte’s bridesmaids dropped the bombshell during the episode, claiming the pair had even slept together the day before he left for the experiment.
Yahoo Lifestyle understands the pair haven't spoken since last year when Harrison called things off to do the show instead.
Abby also confirmed they were no longer together during an Instagram Q&A when one follower asked if anything was still going on between them.
“Not after all the lies he has told,” she replied.
Another user asked if Harrison is “as narcissistic as he’s being portrayed”, to which she said, “What you see is what you get”.
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