I got dual grief, fortitude, arreats, highlords, ravenfrost, dual leech + resist ring, gore rider, laying on hands, and thundergods.
I’m a whirlwind Barb (yes i know frenzy is preferred). Uber Izual - he is dead in moments. Uber Duriel -he is dead in a minute. Uber Lilith - I am dead in a second.
Why is she that damn much stronger and what is the best way to defeat her?
get a pair of draculs or lifetap staff - always keep the “frenzybuff” on and WW her down while she’s cursed. You can close your eyes with this, as long as life tap is on.
Verdungo belt is also great for her massive hits.
Lawbringer offhand works when frenzying - decrep slows things down a lot. Not so sure with WW.
try and lure out into narrow part of coridoor.
Only killed once mind, so might not be amazing advice. worked for me (once).
Life tap curse + crushing blow are your friends for ubers. As Luzifer90 said, Dracul’s Grasp gloves are great. Otherwise you can shop for a wand with lifetap charges and use it on switch, but that can be tedious. 
Or you could build a dedicated uber smiter:
Marrowwalks allow you to self-cast life tap without weapon swapping. Those boots are very handy.
You need block and high dr% for lilith. She can wreck anyone unprepared. Storm shield is your best option.
true but a big loss of CB
OP, this is all you need
you probably have no poison resist or length reduction, and u only have 10% crushing blow, and u don’t have life tap ( aka dracs)
whiel u dont need “all” of that… i would definitely make sure u get life tap from dracs.
or consider swapping fort for a guardian angel.
you need better poison resist
also prebuff with fade,
those are all easy ways to fix this.
now there is something i didn’t know… even after all my years of playing.
( of course that proably has more to do with me maining a fury druid that cant cast spell in wolf form so i would never really need to know this… but im surpised i never heard of this before.
i always hear about lower resist wands or “life tap wands”.
but i haven’t actually heard of using marrowwalk.
it wouldn’t work for me as a wolf, but… that is extremely useful to know!!