Lucas:  "Lindsey, it's just a story. I mean, so what? Peyton's car is just a comet, you know? But this is crazy. I love you."
Lindsey:  "I love you, too, Lucas. I do, and I always will. But your heart is conflicted, and I think I've always known it. I guess I was hoping that someday... I could be your comet. It's an epic love story, Luke. It's just not ours. And neither is this." 
(She put her engagement ring with the manuscript, on the bed and goes to the door)
Lucas:  "Lindsey, please. You can't just leave."
Lindsey:  "People always leave, Luke. You know that.   (She looks at him and leaves)   ~S5/E12