One MerDer moment per episode: 2x24

Meredith: I never should have told you about George. 
Derek: No, its fine, I’m glad I know about him, and the vet. You really get around. 
Meredith: What did you just say to me? 
Derek: It’s unforgivable. 
Meredith: I don’t remember ever asking you to forgive me. 
Derek: So was the knitting a phase? Who’s next? Alex? ‘Cause I hear he likes to sleep around. You two have that in common. 
Meredith: You don’t get to call me a whore. When I met you, I thought I had found the person that I was going to spend the rest of my life with. I was done. So all the boys and all the bars and all the obvious daddy issues, who cared, because I was done. You left me. You chose Addison. I’m all glued back together now. I make no apologies for how I chose to repair what you broke. You don’t get to call me a whore. 
Derek: This thing with us is finished. It’s over. 
Meredith: Finally. 
Derek: Yeah, it’s done. 
Meredith: It is done.