The actress has now filmed her final scenes as surgeon Sahira Shah after deciding to bow out from the BBC medical drama.
Reflecting on her last day on set, Rouass told Daybreak today: "It was actually quite sad! I filmed my leaving scene a few weeks before I actually left, because we don't film in order. But it was really sad being there on the last day. It's like a mourning almost!
"When I started, people said, 'It's going to go by, you're not going to notice' - and I thought, 'No way!' But it has - 15 months has flown by."
Rouass said that leaving the programme was the right decision as she now has more time to spend with her 4-year-old daughter Inez.
"That was one of the main reasons why I had to leave, because the hours were very long - 12 hour days," she explained. "You miss out on so much. So now I've got a bit of time with her, which is great."
Rouass is currently filming a new series of The TV Book Club, which returns to More 4 on Sunday.
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