Earlier this month, Steph chose to die in a massive blaze in the village rather than lose her life to cancer, having been told that she was terminally ill.
In scenes soon to air on the Channel 4 soap, Steph's loved ones will pay their last respects to her at an emotional funeral service, where it becomes clear that Gilly is struggling to cope.
Speaking to Inside Soap about Steph's send-off, Quinlan explained: "Gilly delivers a very moving speech. He's still so angry about the whole thing, so the director asked me not to cry at all during the ceremony.
"It was all so heartfelt, though, that I broke down for real a few times - and I think that's going to come across in the final episode."
Discussing what happens after the service, the actor added: "Lee gives Gilly a DVD with a video message that Steph had recorded for him. It all gets the better of him and he just destroys it. The poor guy's heading off on a very dark journey that I'm sure he'll live to regret."
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