In these brief lines, the speaker announces she will no longer be afraid, either by night or day, now that the person she loves is away. Fear, she reasons, would be useless—what could it possibly change? So she calls herself brave, moving through the dark house alone, methodically locking doors and windows against the wind. The actions sound responsible, but they feel mechanical, drained of real courage. Her heart, she tells us, holds only sorrow; there’s literally no space left for fear.
Then the poem turns sharply. That brave emptiness isn’t a comfort. She wishes, with a cry of “My dear, my dear!”, that she could be afraid again—because fear would mean his presence, the one person who made her world feel secure. The mood is one of quiet desolation: a deep, still grief masquerading as fearlessness. It’s the ache of missing someone so completely that even terror seems preferable to this numb aloneness.