Autumn Within by Henry Wadsworth Longfellow.

It is autumn;

not without,
But within me is the cold.
Youth and spring are all about;
It is I that have grown old.

Birds are darting through the air,
Singing, building without rest;
Life is stirring everywhere,
Save within my lonely breast.

There is silence: the dead leaves
Fall and rustle and are still;
Beats no flail upon the sheaves
Comes no murmur from the mill.