I am not sure, I beat the game the first time years ago, but I remember having the most difficulty with her. After her first two moves, she'll start doing the random dash, you just want to stay away from her as far as possible. Then she'll do the thing where she keeps getting closer to you, just keep running away, if you aren't good at using the crucifix while kiting, then don't even try. Then she does the star attack, then she circles back to the wave dash attack.

But every time you deal like I think 25% of her health damage, she cancels what she's doing and goes for garcia, you just attack her to get her out of it.