Oh admitted that she isn't sure whether Cristina and Owen (Kevin McKidd) have a future following their recent problems.
"It's just sad and hard right now," she told TV Guide. "If there's [hope], I can't see it right now."
However, Oh explained that she is pleased that the troubles are being explored in depth.
"What I really am happy with is that a dissolution of a relationship - if it is a dissolution - takes a long time and is painful," she said. "We're spending time with them, seeing it happen. And not quickly, but painfully, day by day."
Grey's Anatomy airs on Thursdays at 9/8c on ABC.
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