So for the first fight in her house, I positioned my characters around her with my ranger up on the second floor and opened with a bow shot from my Ranger. Got her down to almost half health in first turn. Then she went invisible so we had to just pass turns for one round. When she reappeared we took her down below half and she retreats to her lair.
Once we found her in her lair I tried the same strategy but something must have been bugged because combat would not start after shooting her. She would run around looking for my ranger who kept passing stealth checks and then return to her starting spot. I would shoot her again and same thing, she looks for me, I pass stealth check and she returns to start spot. She didn't even care about the rest of my party and we never actually entered combat. So I just kept shooting her from far range until she was dead. Cheesy and boring but not much I could do if combat wont start after I attack her.
