I'm sick of your world (4)
How is Odysseus' world not Circe's world?
In the same breath,/ I foresaw your departure (15-16)
There's something so formal about the way Circe says, "I foresaw your departure." She could say, "I knew that you would leave," or "I saw that you would not stay," but she reverts to a formal tone. Perhaps she is disguising her emotion at this moment.
Your men with my help braving/ The crying and pounding sea (17-18)
Odysseus can't leave without Circe helping him. But if Circe were to help him, it would mean she would have to let him go. She does just that, and we begin to think that there might be some real, true love involved.