Grey's Anatomy, Season 5

Meredith:
[voiceover] To do our jobs, we have to believe defeat is not an option. That no matter how sick our patients get, there's hope for them. But even when our hopes give way to reality, and we finally have to surrender to the truth, it just means we've lost to today's battle, not tomorrow's war. Here's the thing about surrender, once you do it, actually give in, you forget why you were even fighting in the first place.