I am sure that you and I would drift apart.
5 seconds sound clip from the When Harry Met Sally... movie soundboard.
You can hear this line at 00:51:47 in the Blu-ray version of the movie.
Quote context
[...]
- Oh! I can't believe I'm doing this.
- Look, Harry is one of my best friends and you are one of my best friends.
- You and I haven't drifted apart since I started seeing Arthur.
- If Arthur ever left his wife and I actually met him...
- I am sure that you and I would drift apart.
- You're right. I know you're right. (3)
[...]