They are not those who used to feed us
When we were young--they cannot be -
These shapes that now bereave and bleed us?
They are not those who used to feed us, -
For would they not fair terms concede us?
- If hearts can house such treachery
They are not those who used to feed us
When we were young--they cannot be!

Thomas Hardy

http://www.poemhunter.com/poem/the-puzzled-game-birds-triolet/