Nothing is permanent in life

In the film The Little Buda, of Bernardo Bertolucci, it is showed, in a very poetic way, a budhist principle that it is the principle of the impermanence.
The budhists takes a long time building delicate and complexes of colourful sand mandalas, on the floor, for later, with a firm and definite gesture, destroy them with the hands.
They do it to remind us on purpose that in life nothing is permanent and that we should not depend on things or emotional states to be happy.
We are very special beings, with an incredible capacity to love, forgive, grow and develop. To be truth, the only thing that we really have is the present moment, with its uncountable invitations of development and multiple actions or no-actions.
It is clear that things that make part of our lives are important and beloved but a bit of unattachment bring us enormous benefits.