When Harry Met Sally (1989), directed by Rob Reiner and written by Nora Ephron. Their friendship mirrored Harry and Sally’s excluding the falling in love. Rob Reiner, though, fell in love by the end of the movie.
Peter Bradshaw wrote a fantastic review on it and the re-invention of the rom-com on The Guardian. https://www.theguardian.com/film/2015/dec/10/when-harry-met-sally-rerelease-film-review-nora-ephron