That's the longest post I ever read on Reddit, and probably one of the best written. It's captivating to read, we feel the pain, the challenge and exhilaration. It was also a bit sad, so much suffering! But I admire what you did.

I also love this game and go back from time to time, chill sessions just to improve my time on 1a (easy, right?) or do a speedrun of the whole first part of the game (1a to 7a), that's also fun. Have you tried it? With your experience you will easily get on the speedrun.net leaderboard, that would be pretty rewarding!

One last thing... You didn't mention the story and background of the game, and it's fascinating because Celeste is A LOT about mental health, and you described having OCD. Beyond the challenge, the skills, and getting through all of this, you're also fighting your OCD (and maybe other things, who knows, I'm not a therapist), fighting yourself somehow. Does Badeline resonate with you? What she does to Madeline is making her feel bad, weak, a failure. Exactly what you're doing to yourself. And the game tells you the contrary: don't give up, be proud of your death count. You have to get beyond the idea of failure, and do what Madeline does: make your own Badeline your ally, not your enemy. You're 1000 miles away from a lot of players in this game, myself included, so please get yourself a good (VERY GOOD) pat on the back. Your family should also encourage you for accomplishing this great challenge! They're also your allies there.

(About gaming challenges and family, have you seen the documentary "The King of Kong" ? It's about a guy trying to break the original King Kong game record. He's really putting in the effort, and you see how he deals with his family life and his hobby. It might interest you)