Cheers1982

Sam Malone:
[after a fight about their past relationship, where Diane is about ready to storm out of Sam's office] I'm sorry.

Diane Chambers:
What?

Sam Malone:
I'm sorry. I did the best I could when I was with you. I mean, you're right, I have blind spots, and I'm not a very good boyfriend. I have never tried harder with any woman in my life. I mean, we had some bad times, but I tell you, the good times with you were some of the best of my life.

Diane Chambers:
That's the nicest thing you ever said to me.

Sam Malone:
Diane...

Diane Chambers:
No, Sam, stop. I want to get out of here before you say something stupid that ruins it.

Sam Malone:
Oh, no, no, no...

Diane Chambers:
No, no, no, no, now stop. Don't ruin it.

Sam Malone:
I'm not going to ruin, it. I...

Diane Chambers:
Sh-sh. Sh-sh-sh-sh-sh. [she walks out of the office]

Sam Malone:
[thinks for a second] Oh, yeah, that would have ruined it. Oh, would it ever.