Right you are. I ran across that quote in her collection "The Suppressed Madness of Sane Men". She included the quote but not the paper. I thought it was amazing, so I wanted to read the paper—which was not easy to find. Eventually someone dug me up a copy, and it turned out that the quote was the only interesting thing in it. But what a quote. I don't know of anything more relevant.

If any of you want to explore Marion Milner, the place to start is "A Life of One's Own"- a work of original genius: https://www.amazon.com/Life-Ones-Own-Marion-Milner/dp/041555.... Everyone says "think for yourself" but she actually did it. Oh and her brother won the Nobel Prize in physics. Quite a family.