Originally Posted by Tilean 
If you don't care about co-op in DS3, you probably shouldn't care about DS3 at all.
Though, there is some inventory management in this video here at about 3 minutes in.
Why you dont have to play or use co-op. I know I dont plan on using it. Its just an option from what information there is available about the game. Its not forced on you as the game is still a singleplayer Arpg.