When Odysseus left Ithaca for the Trojan war he was married to Penelope. After that Odysseus traveled to Calypso's island. Not only did he cheat with Calypso in addition to Circe, but he stayed on her island for seven years until Zeus ordered her to release him.

Is Odysseus faithful to Penelope?

He sleeps with two immortal women, Circe and Calypso, while he is away from home. On the other hand, Odysseus is loyal to Penelope because getting back home to her and their son is always his top priority. He may not be physically faithful, but he does seem to be emotionally faithful.

Does Penelope know Odysseus cheated?

Does Penelope know about either of these women? Indeed, she does and Odysseus himself tells her. At Odyssey 23.300-372, Odysseus provides Penelope with a summary of his adventures. He tells her about Circe and Calypso, and even goes into fairly extensive detail about Calypso's sexual desire for him.