Circe's Power Power Quotes

And with those three little words ("with my help"), Circe involves herself in Odysseus' journey, and reminds him of how much he needs her and depends upon her. How would this line be different if those three little words were not inside of it?

That Circe! She's a jokester. Her play on words here does make us think about how weird that phrase is to "hold someone prisoner." What do you think is the tone of these final two lines? Why so think the last line alone in its own stanza?