Grey's Anatomy, Season 2

Meredith:
[voiceover] Forty years ago, the Beatles asked the world a simple question: they wanted to know where all the lonely people came from. My latest theory is that a great many of the lonely people come from hospitals. More precisely, the surgical wing of hospitals. [...] As surgeons, we ignore our own needs so we can meet our patients' needs. We ignore our friends and families so we can save other people's friends and families. Which means that, at the end of the day, all we really have is ourselves. And nothing in this world can make you feel more alone than that.