No going back

No, no, there is no going back.
Less and less you are
that possibility you were.
More and more you have become
those lives and deaths
that have belonged to you.

You have become a sort of grave
containing much that was
and is in no more time, beloved
then, now, and always.
And so you have become a sort of tree
standing over the grave.

~~Wendell Berry

Go here to read the rest of the poem.