I have letters and cards from exs and I'm not even sure where abouts I have put them but in saying that I wouldn't throw them out and would take offence to anyone suggesting that I need to throw them out.
That decesion is mine and mine alone for whatever reason!!! For someone to find these things I would liken that to them snooping...and ask if they would want me to snoop through their personal belongings! he clearly has trust issues and insecurity too...where will it stop??? Will he be reading your text messages soon or just answering the calls so that he knows exactly who you are talking to?