Ovid's version of the tale states that a girl who had also fallen in love with Narcissus made a prayer to the gods, asking that Narcissus suffer from an unrequited lust just as he had done to others. The prayer was answered by the goddess Nemesis - (she who ruins the proud), makes him fall in love with his own reflection so he stares at himself in the river (as he thinks it is a beautiful person underwater) until he turns pale and eventually dies.
Alternatively, Echo was a nymph who was a great singer and dancer and scorned the love of any man. This angered Pan, a lecherous god, and he instructed his followers to kill her. Echo was torn to pieces and spread all over the Earth. The goddess of the earth, Gaia, received the pieces of Echo, whose voice remains repeating the last words of others. In some versions, Echo and Pan had two children: Iambe and Iynx
Don't miss Timberlake Wertenbaker's Echo in The Love of the Nightingale running May 3-29.