The Islamic mystic Rumi says:
“Don’t Grieve.
Anything you lose comes around in another form.
The child weaned from mother’s milk now drinks wine and honey mixes.
God’s joy moves from unmarked box to unmarked box, from cell to cell.
As rainwater, down into flowerbed.
As roses, up from ground.
Now it looks like a plate of rice and fish,
Now a cliff covered with vines,
Now a horse being saddled,
It hides within these, till one day it cracks them open.”

As humans, we fall in love with the forms of life rather than the actual fire of life itself. As infants we fall in love with the bottle that feeds us and cannot recognize the same kindness when offered with a spoon. The baby sees weaning as a time of bitter grief rather than as transition to a more stable form of sustenance.
As adolescents, we seek the love of a suitor. We cannot recognize love when offered by family or childhood friends. Each lover we lose (and we will lose them all) seems an irreplaceable loss if we cannot see the one lover behind them all.

Life contains much change and sadness. We would not be fully human if we did not grieve, but loss reminds the mystic that we are the fire itself, not the form that burns. What we love in the other is in the fire and not the form. We despair of life only because we have left the fire burning at the center of life to chase after ashes blowing in the wind.