The original had me crying. A mermaid that saves the prince's life, fell in love with him, sacrifice her life and voice to be able to see him, prince thought that the girl walking on the beach saved her, married her, and the mermaid was heartbroken and died (turned into sea foam). Moral of the story (maybe): Don't sacrifice yourself for someone you just met.
The prince couldn't have married her if he had wanted to: marriages were arranged from birth and used to forge strict political ties. But how do you explain that to a mermaid, someone from a whole other world, who has no inkling of the surface world and how it works?