Few people who are not deeply rooted fans of Edgar Allan Poe know that Poe wrote his short stories because they brought in funds, that he wrote his poetry it was what he liked to write. Particularly his love poems to his wife.
Anabell Lee is the last thing he ever wrote. It is certainly about his wife's death and it seems to me that it is also about his own death, I believe that for what ever reasons the last lines of the poem indicate that he knew that he was not going to be alive much longer and was at peace with his imminent death.

Anabell Lee by Edgar Allan Poe
It was many and many a year ago, in a kingdom by the sea,
That a maiden there lived, whom you may know
by the name of Anabell Lee
And this maiden she lived with no other though
that to love, and be loved by me

She was a child and I was a child
in this kingdom by the sea;
but we loved with a love that was more then love,
I and my Anabell Lee-
with a love that the winged seraphs of heaven
coveted her and me.

And this was the reason that long ago,
in this kingdom by the sea,
A wind came out of a cloud by night
chilling my Anabell Lee;

So that her highborn kinsmen cam
and bore her away from me,
to shut her away in a sepulcher
in this kingdom by the sea.

The angels, not half so happy in heaven,
went envying her and me;
Yes! That was the reason (as all men know,
in this kingdom by the sea,)
that the wind came out of the could chilling,
and killing my Anabell Lee.

But out love it was stronger by far then the love
of those who were older than we,
of many far wiser than we;
and neither the angels in heaven above,
nor the demons down under the sea,
can ever dissever my soul from the soul
of the beautiful Anabell Lee:

For the moon never beams, with out brining me dreams
of the beautiful Anabell Lee,
and the stars never rise, but I feel the bright eyes
of the beautiful Anabell Lee,
and so, all the night tide, I lie down by the side
of my darling - my darling- my life and my bride,
in her sepulcher by the sea,
in her tomb by the side of the sea.