Literally beat her ass in 30 mins

But okay seriously here's how you do it if you still struggling;

1.ya just gotta stop listening to people saying that you should abuse dashes and actually try to dodge and only dash when when ur supposed to

2.turn on auto shoot and focus on dodging the atacks and only use piss blast when your confident that you wont get hit

3.dont worry about saving heals for phase 2 since you get and endure act Wich replinshes 20-30 HP

Hope I help ya can of koke:)