"Thou wast not born for death"

In John Keats's "Ode to a Nightingale", the speaker addresses both life and death as themes. Throughout the speaker's melancholy, depressing thoughts, the lively song of the nightingale carries on. He wishes to join the nightingale in its carefree life, never again having to worry about the problems of mortal life. To the speaker, the nightingale seems immortal ("Thou wast not born for death..."). The speaker imagines himself with the bird, in an attempt to escape death. This is most likely related to the fact that Keats had lost both his mother and brother to Tuberculosis, and had just begun to show early signs of having the disease himself. This poem is an expression of the imminence of death, in whatever form. Towards the end, the speaker starts to wonder if his imagination has gotten the best of him, and made up the whole situation in his mind. Does this bird even actually exist? Maybe he feels so numb because he is, in fact, sleeping. Or maybe this feeling is what he wishes were truth. He has often thought of death, as he says in stanza 6, "...for many a time I have been half in love with easeful Death...", as a way to escape the pains of life. But then he is brought back from day-dreaming, still not really sure if he is truly awake.