Jealous fiancee'

Everytime i add a new friend thats a male to my facebook or instagram my fiancee waits until i leave the room and goes through my phone and deletes them and he blocks them.and the crazy part is i know these guys i went to school with them i dont add people i dont know to my social network. Its driving me crazy and i just want it to stop we talked about it numerous times and he said he would stop going through my phone but he still does it i dont know what to do if i change my password to my phone he thinks im hiding something so i leave the password the same i cant continue my relationship like this