How does "The Raven" by Edgar Allen Poe relate to Shakespeare's Romeo and Juliet and what are the similarities in their tragic events?

There are common themes of deep, obsessive love and unimaginable loss in the poem “The Raven” and the play Romeo and Juliet. They are both dark, brooding pieces.

The speaker in "the Raven" is a student who is visited by a talking raven one night. The bird reminds him of his sadness and isolation. He recently lost his great love, Lenore. He tries to get his mind off of it, but it is pointless.

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There are common themes of deep, obsessive love and unimaginable loss in the poem “The Raven” and the play Romeo and Juliet. They are both dark, brooding pieces.

The speaker in "the Raven" is a student who is visited by a talking raven one night. The bird reminds him of his sadness and isolation. He recently lost his great love, Lenore. He tries to get his mind off of it, but it is pointless.

Eagerly I wished the morrow;—vainly I had sought to borrow 

From my books surcease of sorrow—sorrow for the lost Lenore— 

For the rare and radiant maiden whom the angels name Lenore— 

Nameless here for evermore.

It is not entirely clear what happened to Lenore, but given the speaker’s misery and Poe’s past, it is likely she died.  She is lost to the speaker, causing him to be severely depressed. Losing Lenore might not be as dramatic as Romeo and Juliet’s demise, but I would argue the love story behind “The Raven” is every bit as meaningful as the one in the play. 

Romeo and Juliet’s deaths were caused by a family feud. They fell madly in love, but had to keep their love and marriage a secret. Then Romeo was banished because of a fight that occurred because of the feud. Juliet faked her death to avoid being forced to marry another man. Romeo does not know Juliet is not actually dead, and life without her seems so miserable that he takes poison and kills himself.

… O, here
Will I set up my everlasting rest,
And shake the yoke of inauspicious stars
From this world-wearied flesh. Eyes, look your last!
Arms, take your last embrace! and, lips, O you
The doors of breath, seal with a righteous kiss
A dateless bargain to engrossing death! (Act V, Scene 3)

Juliet awakens to find Romeo has committed suicide. She then takes her dagger and kills herself. The two are so deeply in love that they cannot bear the thought of being apart. Like the speaker in "The Raven," love is everything to Romeo and Juliet. Its absence is unbearable. The difference is in the degree of their reactions; Romeo and Juliet kill themselves.