Etymologically, this word has overtones of blissful ignorance. Originally, it was word for a medicinal balm, but note: it referred to a soothing drug, not a curative one. The pain lessened or alleviated by nepenthe is never resolved; it is merely repressed, whether consciously or subconsciously.
"But in the cosmos there is balm as well as bitterness, and that balm is nepenthe. In the supreme horror of that second I forgot what had horrified me, and the burst of black memory vanished in a chaos of echoing images."
-H. P. Lovecraft, The Outsider
"Then methought the air grew denser, perfumed from an unseen censer
Swung by Seraphim whose footfalls tinkled on the tufted floor.
'Wretch,' I cried, 'thy God hath lent thee- by these angels he hath sent thee
Respite- respite and nepenthe, from thy memories of Lenore!
Quaff, oh quaff this kind nepenthe and forget this lost Lenore!'
Quoth the Raven, 'Nevermore.' "
-Edgar Allen Poe, "The Raven"