Poseidon had been stalking his wife for weeks since she had put it in her head to defy him. That woman was going to pay for shattering what was left if his soul. She took that little bit of goodness that she had once brought out and laughed in his face. She made fun of his feelings and her rightful place. She was his queen, which meant he was still one level above her. In Poseidon's mind there was only one way to make her his queen again---force her into submission.
He'd seen Thetis before with her husband, acting like children. Fools. Both of them. Now he was certain she and Amphitrite were laughing at him. Their king over the oceans. And he was not to be treated as their entertainment.