The only redemption I could give her is if her story were more complex that "a jerk."
Babs had a reason for her actions, and while her making the CMCs legit cry (especially Sweetie Belle) was frustrating to watch, I still was able to forgive her for her depth and willingness to change.
Gilda, to date, has had no complexity, and wasn't interesting to me, plus, she was a terrible individual.
YOU CANNOT REMORSELESSLY MAKE FLUTTERSHY CRY AND RECEIVE REDEMPTION.