"One of the reasons why I never remarried despite a bewildering range of offers was the determination to never again be ordered around! I must therefore ask you to adopt a less marital tone of voice."

"Regret is an essential component of happiness. "

"As for this present infatuation, it won't last, but for the moment, it's beyond my control"

Like most intellectuals, he's intensely stupid.

this movie had great writing, my favorite part was when Glenn Close gave that whole speech how she became so twisted
so many movies, so little time

That's some mighty praise but the material is totally worthy of it, it is superbly written stuff and the delivery from the actors is terrific too.
My favourite movie for dialogue is
Lawrence of Arabia
, and while it's infinitely quotable I'll admit the dialogue isn't quite as sharp as it is in
Dangerous Liaisons
.

Best dialogue in any film in my opinion. Each line is like a perfect photograph. Instantly classic