EXACTLY!!!!!!! It's implied that Psyche didn't even know he was the prince before she fell in love with him. Why are they blaming her for having regular human feelings? She did not mean to betray Medea with ill intentions, but unfortunately, that was what transpired. Psyche grew up in a basement, with limited knowledge about the world. Medea, although her childhood is arguably equally as cruel - at least had the tools she needed to grow stronger, which psyche did not. Instead of putting Psyche down due to past pre-conceptions, all the vile vitrol should be directed at the prince. for manipulating her innocent nature, whilst also ruining Medea's family.
As much as I agree with everyone saying that Psyche was really frustrating when she didn't refuse the prince's proposal, the girl is being clearly abused and manipulated, and if you're in a position like that you're obviously gonna do whatever you can do to survive, even if it means betrayal. Just try to consider her situation, something must have happened in her past involving "the basement'' that the prince mentioned, and she must have been tortured so badly that now the prince is able to use it against her. And in a way we should be grateful for Psyche's decision to not refuse it, because Medea wont be able to be with the wicked, disgrace of a prince now. Also despite the fact that I really do feel bad for what happened to her nanny, but that problem ain't Psyche's fault. It seems that even if she refused she would have been pulled towards doing it anyways, and Medea's father is the one who did such a bad thing to the nanny. Let's just hope that they're all happy in the end, and the prince and whoever else that did something bad burns in hell.