Who is she referring to in this poem? Thanks

Translated into English by Mary Barnard, this poem is one of the few we still have that was written by Sappho, one of history's most famous female poets. It is told from her own perspective. 
She starts off with a direct focus on a man, but the poem is truly about her love for another woman. 
"He is more than a hero he is a god in my eyes— the man who is allowed to sit beside you—he
who listens intimately 
to the sweet murmur of your voice," 
In this excerpt, the "you" Sappho is referring to is a woman that she clearly has very passionate feelings for. The man in the poem is a "hero," because he can do what Sappho cannot—gain the love and attention of this woman. In context, the titular "He" in the poem is much less important than the woman he sits with, who is driving Sappho wild with desire.