'The Wrath of Hurin' - Where?

Some of the Halethrim did flee to the Mouths of Sirion or some such place (maybe Arvernien), before the destruction of their kin in Brethil. But leaving the leadership of the House of Haleth they wouldn't strictly be Halethrim anymore, in a way. These survivors are the ones that went to Elenna and made with the rest of the Edain the realm of Numenore, but I think by the time they did they were merged with other peoples. The merging atleast occured early on in the history of the Second Age. So some of them, to speak truthfully, did survive.