Grey's Anatomy, Season 2

Meredith [voiceover]:
A wise man once said – "You can have anything in life if you will sacrifice everything else for it." What he meant is nothing comes without a price. So before you go into battle, you better decide how much you're willing to lose. Too often going after what feels good means letting go of what you know is right. And letting someone in means abandoning the walls you've spent a lifetime building. Of course the toughest sacrifices are the ones we don't see coming. [...] When we don’t have time to come up with a strategy to pick a side or to measure the potential loss. When that happens, when the battle chooses us, and not the other way around, that's when the sacrifice can turn out to be more than we can bear.