Poe certainly suffered from real grief. I also like to point out that the bird in the poem is inspired by Charles Dickens. He had a talking pet raven. Sometimes I wonder that the poem is not a clever jab.
You could also look at Poe's personal life as context for the creation of the poem. Poe lost many loved ones (mostly women) in his life to tuberculosis. The lost love of the poem, Lenoire, who is manifested as a raven (of death) could be directly related to the many whom Poe personally lost and the grief he certainly never overcame.
One way of answering this would be to relate this excellent poem to the literary movement with which Poe was associated, which was Romanticism. Romanticism, to use a generalisation, was noted for its privileging of emotion over reason, and in particular, with its focus and emphasis on emotion, to enlarge or even distort everyday emotions into something different. Thus in Romantic literature there are no "mediocre" emotions: joy is ecstasy and grief and suffering are hell. Everything seems to be exaggerated.
Bearing this in mind, we can perhaps see how Romanticism influenced this poem through the speaker's reaction to the death of Lenore. The narrator is a character who is obsessed by grief and seems to be only capable of grieving without ever moving on:
...vainly had I 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...
Although perhaps we might question whether such an obsessive approach to death and grief is realistic, bearing in mind the context, the poem does highlight the way in which death is an eternal reality, and is one of the things that man's art and science have not found a "cure" for, and so perhaps the context can help us understand why the maudlin focus of the poem is appropriate.