What is a thesis statement for The Heart is a Lonely Hunter?

One could be that the main characters all see Singer in as a symbol of hope, mainly for themselves. And that it is ironic that they see this hope in a mute, because in a way, they are all socially "mute" themselves. They cannot communicate properly with anyone but Singer, and the only reason for that is because they project whatever kind of person they want him to be onto him.