If you mean who wrote a poem so called, try Dannie Abse's poem of that title published in 1948
They came into our lives unasked for.
there was light momentarily, a flicker of wings,
a dance, a voice, and then they went out
again, like a light, leaving us not so much
in darkness, but in a different place
and alone as never before so we have been changed.
and our vision no longer what it was,
and our hopes no longer what they were;
so a piece of us has gone out with them also,
a cold dream subtracted without malice, the weight of another world added also,
and we did not ask, we did not ask ever
for those who stood smiling
and with flowers before the open door. We did not beckon them in, they came in uninvited,
the sunset pouring from their shoulders;
so they walked through us as they would through water,
and we are here, in a different place,
changed and incredibly alone,
and we did not know, we do not know ever.