From Elizabeth Gilbert in her book Committed: A Skeptic Makes Peace with Marriage
Modern Americans bring to their marriages the most over-stuffed bundle of expectations the institution has ever seen. We expect that our partner will not merely be a decent person, but will also be our soul mate, our best friend, our intellectual companion, our greatest sexual partner and our life’s complete inspiration. Nobody in human history has ever asked this much of a companion. It’s a lot to ask of one mere mortal, and the inevitable disappointments that follow such giant expectations can cripple marriages.