The author is probably describing some invincible feeling of guilt - "It's in my head". It seams to me that "nightfall" is allegory of death, then it's clear why it can "release" and lead to "deep sleep".
A picture which come to mind is a soldier who shattered a lot of lives. He regrets it but he cannot stop killing, because otherwise he must die himself.
The author is probably describing some invincible feeling of guilt - "It's in my head". It seams to me that "nightfall" is allegory of death, then it's clear why it can "release" and lead to "deep sleep". A picture which come to mind is a soldier who shattered a lot of lives. He regrets it but he cannot stop killing, because otherwise he must die himself.