Sonnet LVIII - What Lips my Lips Have Kissed

Edna St. Vincent Millay - 1892 - 1950 was one the country's most successful and respected poets.  Her popularity, however as a poet had at least as much to do with her persona.  She was known for her progressive political stances, frank portrayal of both straight and gay experience, and above all her embodiment and description of new kinds of female experience and expression.
What Lips my lips have kissed, and where,
and whyI have forgotten, and what arms have lain
Under my head till morning; but the rain
Is full of ghosts tonight, that tap and sigh
Upon the glass and listen for reply
And in my heart there stirs a  quiet pain
For unremembered lads that not again
Will turn to me at midnight with a cry
Thus in the winter stands the lonely tree
Nor knows what birds have vanished one by one
Yet knows its boughs more silent than before
I cannot say what loves have come and gone,
I only know that summer sang in me
A little while, that in me sings no more.