Yes this gets very annoying real fast.At this point the value of sneak skill and
a bow comes in handy. I had both chars setup as bow persons cause i kept getting killed by stone bitters. Get a few levels of sneak and use a bow. you can see them
at a distance and wack'em. Stay outside of the red zone and they can't see you.
Worked with final boss using ethereal arrows, was easy. Would work using any ranged attack (magic). regards.