This has been my experience too. She's also immune to your stun (Green Sleeves), but that's not too surprising. (I still haven't found a use for it, to be honest.)
After a bunch of tries I was finally able to win via kiting and luck:
I tried rearranging my items to increase my Guard stats as far as I could and quickly got perma-stun-locked in a couple of attempts. (Also my Escape was down to 2, which doesn't bode well for that mid-fight grab.) I don't necessarily mind doing some grinding if certain stats are needed, but is there some in-game way to find this out that I missed?