Find the broken heart and heal it.
The Fae spirit felt the great ship above it. There was so much love there, so much kinship. All who breathed on the ship had someone in their life that mattered. All, but one. That must be the one that the summoner meant. The spirit swam around the ship and gathered the heartbreak and sorrow from those who had lost. Then, it drew the sadness and pain away, as requested. It swam off, making a vacuum that would be filled with the caring it could sense was there. When it surfaced, it would cast away all the bad stuff and there would be nothing to stop them from yielding to their feelings.
The spirit was pretty sure that was what the woman had intended.