The speaker can't stop thinking about someone, and the poem is a question about whether that will ever end. The opening, "Will it stop?", sets a tired, almost whispered tone, and the casual lowercase style makes it feel like a private thought rather than a polished statement.
What makes the poem painful is the choice the speaker faces. Keeping the thoughts alive brings small moments of happiness, since the speaker smiles when the memories linger. But the speaker also sees this as self-harm, a way of holding on to someone who feels "so far but so close." The other option is to let go and face days of sadness, which would eventually leave the speaker lonely. Neither path feels good. The poem suggests someone caught in longing, afraid that moving on means losing even the comfort that hurts them. The mood is quiet, confused, and heavy, ending without any answer.