Thus Spoke Zarathustra discussion

Hi,

I recently read a quote on GoodReads:

“It is not a lack of love, but a lack of friendship that makes unhappy marriages.”

- Friedrich Nietzsche

In which book does this quote appear?

PS: I added some book by the author, as the site did not permit me to post the question otherwise...

I gave it a shot and checked the indexes of all Nietzsche's major works for "marriage" and "friendship" and came up with nothing that resembles this quotation. Do you think it's possible that the quote appeared in epistolary correspondence or a lesser known work? Some quotes I came across came close to the one you're after say in Thus Spoke Zarathustra and Beyond Good and Evil, but they weren't exact enough. I empathize with your frustration. The closest quote I came across was in his Human, All Too Human, Volume I, aphorism #378...perhaps it was translated differently and it morphed into your quote?