Quaff, oh quaff this kind nepenthe and forget this lost Lenore!" (line 83)
This is the height of his grief. Here, love loses the battle for a moment, and he only sees despair. In that moment he imagines a magical solution to his pain, a potion (nepenthe) that would take away his sorrow, make him forget forever. This is sort of depressing, isn't it? He seems a little hysterical sometimes, or maybe a little self-absorbed, but in moments like this, it's hard not to feel bad for our speaker.
Tell this soul with sorrow laden if, within the distant Aidenn, It shall clasp a sainted maiden whom the angels name Lenore – (lines 93-94)
Then, just as we feel like we're headed straight to the bottom, like nothing will ever get better at all, we get a little ray of hope. Suddenly, the possibility of love comes back. What if maybe, in heaven, grief will end, love will triumph, and he and Lenore can be happy and "clasp" each other forever? This is as close as he gets to saying not just that he misses Lenore, but that he loves her too. Of course the Raven goes ahead and squashes this tiny bit of hope like a cockroach. It requires only his favorite line: a single, devastating "Nevermore."