What role does hope play in our lives?

Hope is the idea that something in the future might happen. Hope carries an element of optimism that the future event, whether in this life or the next, will be beneficial. Human life is challenging; we face and fear mortality and are constantly dealing with loss. Hope is one thing that keeps us going in the face of our troubles and struggles. 
Hope also contributes to our sense of purpose in life. If life is only struggle, people have a hard time being motivated to do the things they need to do. Hope leads us to work harder at work in hope of a raise or promotion, to love more deeply because we hope we will be loved back, to work for eternal things that will influence what happens beyond our death. That may be based on religious beliefs about the afterlife or the desire to leave an earthly legacy. Hope can be a tiny, sweet feeling that keeps us going even when we are facing the storms of life.
https://www.poetryfoundation.org/poems/42889/hope-is-the-thing-with-feathers-314