I'm not quite sure how to phrase this, but what are your feelings on Cassandra and Apollo's relationship?
Okay, this is really, really hard to explain. Except that I think everyone else is wrong. I am going to give you an answer, but it is not going to be a complete or adequate one.
He is her god. She is his priestess. She calls herself his latris, his servant. She is devoted to him. He has also hurt her immensely, he has also caused her unbearable suffering.
She wears his garlands, carries his sacred staff. She calls him her philtatos, her dearest, her beloved. She also calls him her destroyer. She addresses him constantly; he is always with her, she can always feel his presence.
She was trying to consent to him, and could not. ξυναινέσασα Λοξίαν ἐψευσάμην, “In consenting to Loxias I lied.” The consent and the deception happen at the same moment; she does not make a promise and renege on it, it’s nothing so simple as that. Consenting to a god is difficult; sex with a god is unlike sex with a mortal. He overwhelms her with his sheer physical presence, with the intensity of his divinity, breathing charis upon her body. She cannot accept him. It is like a test she failed. He punishes for it, and this is a terrible cruelty, it is a disrespect against her own bodily autonomy. It shows that he believes there is no part of herself she should hold back from him.
It is cruel, but he is a god, and the cruelty of the gods is unlike human cruelty. They rarely respect mortals’ autonomy, their right to control their own bodies and their own fates. His cruelty is to be expected.
The text makes it difficult to tell whether he rapes her, or whether, at her refusal he steps back and leaves her body alone. I don’t know. It could be either.
One critic says that her rejection of him is about a refusal to bear his child in her body, arguing that she is one of the few women desired by a god who does not bear a divine child.
Even if she denies him access to her physical body, he is always within her. That is what prophecy means, this is what it means to be his priestess. This is its own, unique type of intimacy. He gives her visions which are agony. And she also experiences the joy and glory which is his presence.
She laughs, and sings, and invites him to lead her to Agamemnon’s bed: άγε συ Φοιβε νιν, κατα σον εν δάφναις ανάκτορον θυηπολω, “You, Phoebus, lead me; among the laurels I offer sacrifice at your shrine.” This means: “Look what you have done to me, take responsibility for it.” This means: “Look how I serve you still, even when you have forsaken me.” This means: “Help me find joy in my subjugation.” This means: “I love you.”