Orfeo ed Euridice. Euridice exists only to create the story of Orfeo.

Che farò senza Euridice, Orfeo's aria from Orfeo ed Euridice

Che farò senza Euridice  What will I do without Euridice
Dove andrò senza il mio ben. Where will I go without my wonderul one.
Euridice, o Dio, risponde Euridice, oh God, answer
Io son pure il tuo fedele. I am entirely your loyal one.
Euridice! Ah, non m´avvanza Euridice! Ah, it doesn´t give me
più socorso, più speranza any help, any hope
ne dal mondo, ne dal cel. neither this world, neither heaven.

Translation by Gabriel Huaroc (ghuaroc@usm.edu.ec)

From the flute tunes page:

According to Greek mythology, Orpheus was “the father of songs”: with his music and singing, he could charm birds, fish and wild beasts, coax the trees and rocks into dance, and even divert the course of rivers.

When his wife Eurydice died of a snake bite, Orpheus played such sad songs and sang so mournfully that all the nymphs and gods wept. On their advice, Orpheus traveled to the underworld and by his music softened the hearts of Hades and Persephone (he was the only person ever to do so), who agreed to allow Eurydice to return with him to earth on one condition: he should walk in front of her and not look back until they both had reached the upper world. He set off with Eurydice following and in his anxiety as soon as he reached the upper world he turned to look at her, forgetting that both needed to be in the upper world, and she vanished for the second time.

It is then that Orpheus intones the lament, “Che farò senza Euridice?” (“What will I do without Eurydice?”), a sublime aria which has truly become immortal.

 http://www.flutetunes.com/tunes.php?id=236