Who is Aldarion from Unfinished Tales of Numenor and Middle-earth and what is their importance?

Also known as Tar-Alderion, Aldarion is the son of Tar-Meneldur seen in the tale of "Aldarion and Erendis: The Mariner's Wife." He is a man with the best of intentions that does not have the strength to stand against his love for the sea. Aldarion cannot find the balance for the great loves in his life. While he eventually becomes a great king for his people, he loses his family in the process.