Does the speaker seem to change in "The Raven"? If so, how would you describe his feelings?

The narrator in Edgar Allan Poe's poem "The Raven" does indeed go through many emotional changes during the course of the poem. "Weak and weary," the narrator is nonetheless awake during the middle of the night, reading a book about ancient history in hopes of alleviating the misery he feels for his lost love. 

... --vainly I had sought to borrow / From my books surcease of sorrow--sorrow for the lost Lenore--

As he tries to nap, a noise is heard. The narrator becomes nervous, wondering about the cause of the sound. It is a raven, which flies inside and perches on a statue. At first the narrator is happy to have a visitor...

Then this ebony bird beguiling my sad fancy into smiling, / By the grave and stern decorum of the countenance it wore...

and finds such humor in the situation that he speaks to the bird.

"Though thy crest be shorn and shaven, thou," I said, "art sure no craven, / Ghastly grim and ancient Raven wandering from the Nightly shore--/
Tell me what thy lordly name is on the Night's Plutonian shore!"

When the raven answers, "Nevermore," the narrator is filled with wonderment and begins a conversation with his new friend. But the narrator becomes perturbed with the bird's continuous reply of "Nevermore," and when the bird later fails to answer him, the man's overwhelming sadness causes him to become unglued. When he asks if he will ever recover from his lover's death, the raven once again answers in the same manner.

The air becomes "denser," and the narrator "shrieks," "cries," "implores" and then "shrieked" at the bird to rid him of its evil presence. He seems near madness.

"Be that word our sign of parting, bird or fiend!" I shrieked, upstarting-- / "Get thee back into the tempest and the Night's Plutonian shore! / Leave no black plume as a token of that lie thy soul hath spoken! / Leave my loneliness unbroken! --quit the bust above my door! / Take thy beak from out my heart,and / Take thy form from off my door!" "Quoth the Raven "Nevermore."

The speaker's sorrow apparently will go on, and his "soul" is lost forever.