Meredith and Derek eventually break up again, and Derek briefly dates Nurse Rose. The former couple remain professional as they run a clinical trial together. After their last patient pulls through, Meredith celebrates with one of the show's sweetest (and cheesiest) gestures ever in season four's finale. She creates a blueprint of their home together out of candles. Ida Maria's sultry "Keep Me Warm" creates a tender atmosphere that'll make you swoon hard.