if all else fails delete the game and reïnstall it (your savegame will remain in the cloud so you can go on where you left off when its reïnstalled).
the thing you describe however, i have had similar problems when playing co-op in my friends world. sometimes after a while (when we get thralls at the lake in the north) on the way back all resources abd trees etc. are invisible.
they are still there, just cant see them. thos causes me to bump into everything and having to follow his footsteps to get to the wheel of pain before disconnecting and reconnecting to fix it.
he does not have this problem.
reïnstall game, your savegame will remain in the cloud you will not lose progress. (unless you play online and reïnstalling takes longer than 6 days.)