I have broken away from them, but O heart, I am terrified of your stubborn self-will and obstinacy.

This couplet beautifully captures the fragile moment just after walking away from someone you love. You might have gathered the resolve to separate, but the heart is notoriously stubborn and answers to no one. The speaker's real dread isn't the distance or the other person, but the fear that their own rebellious heart will sabotage this hard-won decision and pull them right back.