Calypso In Exile by Derek Strahan

On the death of Poseidon, Calypso and her sister Circe are exiled from Atlantis by the new ruler, their father, Atlas, for unruly behavior and for practicing magic. Each now inhabits an isolated island. Circe forms a political alliance with the Amazons and Gorgons to defeat Atlas, but Calypso, consumed by her love for Ulysses, brings about a different ending to this ill-fated venture.