Can’t graduate High school

Hello everyone! I don’t really know how to start this. I guess i should apologise in advance for my messy grammar and writing.

I am currently 19 (F) and i was supposed to graduate school this summer, but i failed because of 2 specific subjects that required 2 giant projects. One is art, and another is media. For media I was supposed to film a short movie.
Art and media are the only subjects i have ever enjoyed and that I’m best at. I was the best than anyone else in my school in these subjects- my teachers told me, my parents and even my classmates that never liked me. I also scored A’s on mock exams etc.

Naturally, everyone believed me when i kept telling that i got it, that I’m working on these projects and that I’ll send the proof soon. I never did. Instead, i spent hours on doing whatever stuff that helped me to forget about school. I sometimes didn’t sleep for 3 days straight playing some dumb games that are not in the slightest interesting. I don’t even enjoy playing them.and then, of course, everything collapsed and i failed to complete my diploma.
Luckily, i still managed to get into a university under some program that allows you in as long as you’ll complete your diploma later or something- I don’t quite know the details. After these events, i was diagnosed with AUDHD at 18 just this summer and started therapy regarding autism in July.

So far i really enjoyed uni: i moved out, i cook for myself, my roommate is really great and i have been even enjoying some assignments- i guess its because my course aligned perfectly with my skills, with the stuff that I’m best at and because i am by my own and no one controls me. The thing is, I’m supposed to complete my school diploma now(during autumn). I also enrolled for a very easy exam to get an extra point in my diploma just in case. Today, my mom called me and it came out that I should’ve been at my school for this easy exam today. And it feels like everything is collapsing all over again. This didn’t happen because I forgot or messed up either the dates or something. It happened because I couldn’t bring myself to look at the exam dates and see what my deadlines are. I still can’t. I’m almost sure it’s in the first half of October but I don’t really know. I feel like an idiot and like a burden. I have a psychotherapist, i have loads of loads of meds, i have my mom and the support of anyone if i only asked. But I can’t even take my meds daily because it feels like a demand. I need to start doing something, I need to ask for help but i am paralysed with terror. I’m so so scared. I feel Iike I’m ruining my life that didn’t even begin yet and honestly, I would’ve let that happen if not feeling sorry for my mom that gave me so so much already.

I feel as if the life is a highway, and as if people are riding through it in their cars peacefully, while I’m a reindeer that tries their best to cross it while constantly dodging semi trucks. But i suck at dodging. Most of the times i just freeze and wait until the inevitable happens. And a part of me that I’m trying to run away from doesn’t want to try and dodge the trucks . A part of me wants for a roadkill so brutal to happen that trying to stand up again wont be possible so i can just lay there with all of my bones broken in peace. But I can’t do it to my mom and to 3 of my teachers that helped me to stand up last time.

If you were in a similar situation, i would appreciate any advice deeply, because in my situation the usual advices “to avoid” stressful environments aren’t quite possible.
I hope that I didn’t sound like I’m victimising myself. I also feel very guilty because i know that i have more resources than most of the people. I’m really desperate.