Gratitude is the inward feeling of kindness received. Thankfulness is the natural impulse to express that feeling. Thanksgiving is the following of that impulse.
Sometimes we need to remind ourselves that thankfulness is indeed a virtue.
Thankfulness is the beginning of gratitude. Gratitude is the completion of thankfulness. Thankfulness may consist merely of words. Gratitude is shown in acts.
Some of the writers I admire who seem very very funny and very emotional to me can develop a closeness with the reader without giving too much of themselves away. Lorrie Moore comes to mind as does David Sedaris. When they write the reader thinks that they're being trusted as a friend.