Changing metaphors

If you do change the metaphor half way through the poem the change should represent change itself. Starting with LOVE IS A JOURNEY e may change the metaphor to LOVE IS A LONG DISTANCE RACE with images of struggle, uphill battles, not lasting the distance, rivalry, etc.

youth, gone by

no message of thanks
like dropped stone into black well
waiting for an echo
complete silence
as though my letter
had never reached him
or else it had gone straight past

youth, selfishness
same thing
common curtesy out all windows
but i cannot be angry
all i can do is write a poem
for i was as young and
more selfish once