A quote from Henri Nouwen:
One of the arguments we often use for not writing is this: “I have nothing original to say. Whatever I might say, someone else has already said it, and better than I will ever be able to.” This, however, is not a good argument for not writing. Each human person is unique and original, and nobody has lived what we have lived. Furthermore, what we have lived, we have lived not just for ourselves but for others as well. Writing can be a very creative and invigorating way to make our lives available to ourselves and to others.
We have to trust that our stories deserve to be told. We may discover that the better we tell our stories the better we will want to live them.
from Bread for the Journey