Calypso is upset because she thinks that he wants to leave and go to his wife.
"Can I be Less desirable than she is? Less interesting? Less beautiful? Can mortals compare with goddesses in grace and form?"
Odysseus is trying to explain to her that his wife doesn't even come to close to her and that he wants to leave so he can return to his land.
" My goddess here is no cause for anger. My quit Penelope how well I know would seem a shade before your majesty, death and old age are unknown to you, while she must die. Yet it true each day I long for the sign of home."
She grants him his wish and allows him to leave to return back to Penelope.