Pain for the master... #poem

Pain for the master,
As the student grows old.
The parts are now ended,
But the hearts are still open.
The lost, once befriended,
Are contacts, now broken.
As the world's unfurled,
With its kindest dementia,
And the mentor wanes,
In the evening shadows,
And the gains, of the age,
Still remain there, in tatters.