Most might remember "Lift Love Letter" as one of the best Meredith and Derek episodes where the latter proposes, but it also has a powerful subplot featuring Cristina. While they're sleeping one night, Owen chokes Cristina, which is a manifestation, we later find out, of his PTSD. The episode delicately and complexly addresses Owen's mental health while teasing out the nuances in Cristina's reaction after the incident.
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