You say that the day of union was cut short, but the night of separation has been severed.

This couplet beautifully captures the aching disparity between joy and sorrow. The speaker is responding to someone who minimizes the pain of separation, claiming the day of union was enough. But the heart knows the truth! The memory of the night of parting—the agonizing wait, the tears, the emptiness—is so profoundly painful that it eclipses the sweetness of the day. It's a universal lament about how the ache of loss often outlasts the warmth of happiness.