Life, Janet Leigh as Marion Crane from Psycho (1960)

Norman Bates: You know what I think? I think that we're all in our private traps, clamped in them, and none of us can ever get out. We scratch and we claw, but only at the air, only at each other, and for all of it, we never budge an inch.
Marion Crane: Sometimes, we deliberately step into those traps.
Norman Bates: I was born into mine. I don't mind it anymore.
Marion Crane: Oh, but you should. You should mind it.
Norman Bates: Oh, I do

- Janet Leigh as Marion Crane from Psycho (1960)

AFI #056 Anthony Perkins as Norman Bates from Psycho (1960)

Marion Crane: Do you go out with friends?
Norman Bates: A boy's best friend is his mother.

- Anthony Perkins as Norman Bates from Psycho (1960)

The bolded line is ranked #56 in the American Film Institute's list of the top 100 movie quotations in American cinema.