Because, dear friend, you and I are like that red wall
Carrie: I can't.
Mr. Big: Why?
Carrie: Because, dear friend, you and I are like that red wall. It's a good idea in theory, but somehow it doesn't quite work.
"And just like that, I realized Big and I weren't "us" any more. We had become something else. What it was, I had no idea."