Removal of my survival map without touching it

When i started my game , i joined my survival map ( 1.4GB ) , it took a lot of time to start when this does not happen. Then at once my game has freeze and crashed. So i restarted my game like anyone else, then i wanted to relaunch my survival map but it didn't appear at all, as if it had disappeared. I just want to get my map back because i'm very committed to it and i'm making a lot of effort. Thanks for helping me get the map that i'm not deleted, who, though, disappeared...