The lines you refer to are from Feste's song in Twelfth Night, where the character expresses sorrow over love that is not returned. The use of "Come away, come away, death" reflects the speaker's deep despair, wishing for death as an escape from the pain of unrequited love. The mention of being laid in "sad cypress," a tree often associated with mourning, reinforces the theme of sadness and loss, rather than a preference for death itself or a cypress coffin.