What u also can try, is to take the Stun Arrow and see if u can stun her, then Rush Attk her and Thousand strikes with other skills, should bring her down quite some. or if she's got some enemies with her, try to charm some of them, and let them get the most of the damage. Since pets are indeed a huge damagesponge, especially your pet u summon through the crystal skull can get a nice Melee/Magic Resistance with the proper bodyparts.
