Her chasing Necromites in the 2nd hal of the 2nd fight is not that stupid, as she blows her Smites on Kethric in the 1st half.
Well, there was that one time when she blew those Smites on me, as she was Dominated by the Illithid
If down to 1HP and inside the Bonechill Aura I Shove or Throw her out, to allow her to recover and hopefully chase the Necromites, instead of charging back at Kethric.