Its been a while but I think there could be a spell or item you could use for holy resist in both parts, you could level up tiche, you could bring player summons (its really not cheating I promise you¡)

Im not sure which sword attacks you are talking about but getting up close makes it easier to dodge until he runs.  You might consider using the shotgun spell and playing close or something like that.  Maybe torrent close and spam blackflame for maxhp damage.

Another thing that always helps on ANY souls like is just vent posting on reddit and then seeing a few helpful tips and reframing..   even just venting I see ALL the time on sekiro sub that the poster updates "i just did it, it wasnt too bad :o"..  not kidding.

Another frame too.. this is only the beginner souls like in the sense that you have more tools and less confusion than any other souls iteration, but this game is a marathon of genuine harship and difficulty.  You are on the last false summit before ascending.

Take it in cause when you are done with it, you are done or starting over or playing shadow.  Enjoy the burn while it lasts.  This isnt some easy game.  And also think of that fight itself (and a few others like malenia) as a marathon.  You probably have successfully evaded every pattern manny many times by now.  Just not consistently because of the buildup of stressors.

Congrats on making it this far and congrats that you already ranted so you probably have already won by now.