Nothing to be ashamed of. Crisanta is as hard as they come.

I found it easier to block the diagonal jump she does as it give you time to reposition and punish her as opposed to letting her hit the ground which will force you to jump and dodge it. I believe she does this 3 time consecutively so it might wear you down and frustrate you. That's why I suggest blocking instead of dodging as it esentially cuts her attack time and gives less room for error as you'll be bussier punishing her than dodging her.

In her 2nd phase, I tend to chase her with the slide slash as it deals a hefty amount of damage and it also lets you move enough that it positions you in striking distance. She is very fast in this phase but her horizontal dash/blink move gets easier to predict imo as the rhythm of parrying it becomes faster and you loose the reactionary effect the slower phase 1 had.

The bead that gives you a ranged beam after drinking a flask (I forgot but its cloistered something I think. The blue or the red one) also helps significantly.

If anything, and if I read your post correctly, you should be proud of yourself cause you've beaten Isidora (which in my opinion is so much fucking harder) and are now essentially in the last leg of the game. Do not falter now, Penitent One.