For the whole thing about matrimony is this: We fall in love with a personality, but we must live with a character. Behind the pretty wallpaper and the brightly painted plaster lurk the yards of tangled wire and twisted pipes, ready to run a short or spring a leak on us without a word of warning.
Peter De Vries (1910-1993) American editor, novelist, satirist
Mrs. Wallop (1970)
(Source)
Often misquoted as "The difficulty with marriage is that ..."