Leucothea

Leucothea was originally a mortal named Ino, daughter of Cadmus, king of Thebes. She married Athamas, king of Orchomenus, who, incensed at her unnatural conduct to her step-children, pursued her and her son to the sea-shore, when, seeing no hope of escape, she flung herself with her child into the deep.

They were kindly received by the Nereides, and became sea-divinities under the name of Leucothea and Palæmon.

From: Berens, E.M. The Myths and Legends of Ancient Greece and Rome. New York: Maynard, Merril, & Co., 1880. Text in the public domain.