http://800support.net/facebook-support/ It is not necessary that to hide your conversation from someone on Facebook the
only option you have is to delete it permanently. As you may require them in near
future and then it won’t be possible to get them back if they are permanently
deleted. https://www.facebook.com/Tuyet-L-Schade-497173883801352/, https://twitter.com/tuyetl_schade