The 29-year-old, whom it was recently announced would leave the soap after just 15 months on air, will make his final appearance on Australian screens in a few weeks' time.
"Well, it wasn't my decision," Coleby told TV Week. "But I'm happy about it now. I can see why they decided to end the Roman character. He had a finite story arc.
"There was always something about Roman that was a bit dark, so they explored that and unfortunately went too far for him to carry on."
Speaking of his time with the series, Coleby added: "It's been great from day one. It's sad that I won't get to see everybody every day. I'll miss everyone. There's such a nice family vibe on Home and Away."
Coleby is currently dating co-star Esther Anderson, who plays controversial policewoman Charlie Buckton.
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