I finally stopped playing the game about an hour ago. But I was beginning to see the wisdom in how this particular quest was designed. Yes it's difficult to fight through these "ghost trappers" and other whatevers bouncing around, chucking spears and being difficult as hell to kill. They also have a tendency of coming back to life to attack once again, like the villain in horror movies. So it's necessary to double-check and make sure each baddie really is dead.
But as I fought through the same map over and over again, I began to see that the map itself has designed into it little things to help the player along. In clever little inconspicuous places along the winding route there are ways to regain health points quickly. And it is possible to use the lay of the city against the enemy. There are plenty of large columns to hide behind and attack from. But I've also noticed some propitiously placed stairways which give my character the advantage of the high ground, and which are also narrow enough to restrict multiple attackers from coming up at me at the same time.