A phrase can be used so frequently in a novel that quoting it becomes a coded signal you’re a fan of the book. The best example is ‘So it goes’ from SH5. It’s a motto, a tattoo, a stand alone Reddit post comment. For those who can’t place the quote it also serves as a cultural shibboleth.
But the only other ones I can think of are ’Es muss sein’ from TULoB and ‘Oh my valves!’ from CoD. (Why are all three words?!) But there must be others. I don’t mean famous one liners, I’m talking about multiple uses of a phrase. Can anyone mention another?
The Catcher in the Rye uses repetition of various phrases in not quite the same way as So it Goes or Pootiweet, but they are repeated much more often to the point the repetition itself becomes a literary/commentary device.
___ killed me! Is the one that I can think of.