If you don't like resting really often and don't like how much easier that makes the game, but you also want to experience the companion story, which is a significant aspect of the game, then you're out of luck.
As far as difficulty goes, there will be higher difficulty levels to pick at launch if the game is too easy for you. I would think in general they would balance the game around resting the amount of times needed to see the companion scenes (not including current bugs with the scenes, which will hopefully be fixed).
