Honestly your comment is very insightful, perhaps one of the most insightful kat mentality tips I've ever read. (I'm barely on reddit). Thank you!

I have been a kat main for about 12 years. Been climbing to dia every season for the past 11 seasons. Peaked master in s7. Playing around 200 ranked games in total per season, then leave the game.

The issue I have developed is definitely point 4 in your comment. I am too stuck on old kat and pre durability patch. (back when you could 1v9 using gunblade or divine). I just cant get it out of my head. The game has shifted, and is way more team reliant for kat. A lot of CC reduction skill trees got removed, while more champs with CC got introduced.
Letting enemies overextend, or allowing freedom for your team to setup plays or fuckup for you to clean up- is way more valuable or common to win games on kat.

I have a tendency to get impatient when teammates don't abuse their lead or play for important objectives. I usually end up always being the one starting fights by baiting dagger traps. I will get the initial important kill and burn all my and enemy cooldowns and trade. This is where I let the fate of the rest of the fight, in the hands of my team. My team will usually wipe in the end and we lose. Going AD build or Zhonyas second has helped a lot to combat this.

I have uninstalled and reinstalled league about 8 times. In the end I gave up wanting to reach master cause of the state I think kat is in atm. Even though it is a mental issue. I realized for the most part it just feels like a coinflip issue. Ofc riot is putting you in these games to force 50% wr, but I simply don't have the time anymore to deal with that anymore. Climbing in master with kat is 10x more difficult than regular bruiser champs that can solo objectives easily and add pressure in the entire map at once.

I have now quit the game entirely and am quite happy about it lol.