The two goddesses with whom Odysseus has extended affairs are similar in that Circe is a devastatingly beautiful goddess-enchantress and Calypso is a devastatingly beautiful goddess-nymph; but they contrast in their motives toward and treatment of Odysseus. After Odysseus (following Hermes' advice) initially conquers Circe, she does everything she can to help him. In addition to releasing the spell that turned his men into swine, she is such an excellent hostess and lover to Odysseus that his men must talk him into going on with the journey a full year later. Even then, Circe helps the Greeks with supplies and advice.
Calypso, on the other hand, is an egocentric, dominating goddess who holds Odysseus captive for seven years in hopes of marrying him. When he resists and is liberated by Hermes under orders from Zeus, Calypso offers him immortality if he will stay. When he declines even that offer, Calypso leads Odysseus to believe that letting him go is her idea: "I am all compassion," she lies (5.212). While we may admire Calypso's spunk and her very early advocacy of women's sexual equality, her possessive obsessions make her more trouble than she is worth for Odysseus.