missing out

this is kinda personal and ive talked abt it before so feel free to ignore 

im 21 now. its been 3 years since i dropped out of highschool. i went into psychosis and couldnt be around ppl anymore. i wasnt exactly popular in highschool. i was the autistic person ppl would post on their instagram story to get likes. i mean i had to leave. i had literally 0 friends. 

but oh god sometimes it eats at me. im never gonna have another chance to go to prom, to walk up on a stage in a cap and gown and get my diploma. that experience was stolen from me. yes i know its silly to be sad about it but i dont know how to stop

 i know theres parties and graduations at college but i dont know, it just wont be the same. 

i feel like a bitter old hag. i see teens posting their prom or graduation photos and i block them instantly. ive even cut ties with my little sister because she got to do what i couldnt. 

am i doomed forever? or am i too old now and i should just get over it? maybe this is something serious i need to work out in therapy? or maybe i have way too much time on my hands from being a neet hikikomori and im focusing on shit that doesnt matter.

oh well. i dont have the answer today but maybe someday ill be able to not flinch every time i see a cap and gown 

yes you need to work this out in therapy. everything experienced too late becomes poison especially in today's world. i feel how you feel about ppl experiencing stuff you didnt and you getting bitter about it. same honestly. 

(I'm not sure if you're actively looking for a response, the last time I responded to someone's vent like this, they told me to fuck off and I unfriended them, but)
I think the cliché thing to say would be that a lot of those high school things don't really matter in the grand scheme of things; your experiences in high school don't dictate the rest of your life, society/the media overromanticizes youth and teenage years, et cetera...You'll probably have people reply to you with something like this, even

I really don't like when people say things like ^ though, since also, you shouldn't write those things off, it is important to have those formative experiences when you're young, and it's normal to feel like you missed out (Hell, I graduated and I got screwed out of Homecoming and Prom every single year for reasons that were outside of my control, partially because I was in high school during the pandemic, so I can relate), but I guess what I'm trying to get at is that you shouldn't paralyze yourself if you missed out. Life goes on regardless. Allow yourself to feel sad and all, give yourself time to heal, but remember that you have to keep moving forward at some point.
It's never "too late" unless you're dead.

I don't know if the "falling out" you mentioned with your sister was particularly ugly or anything, but I would suggest making up with her if you can. A sisterly bond is something I'm quite envious of,  I think you should treasure something like that if you can...

I hope this doesn't come across as self-conceited, but if I may talk about myself for a bit, I also feel like I missed out on a ton of formative experiences in my teenage years (I never really spent time with friends outside of school, I never dated or had a girlfriend, I didn't get my license until I was 21 and I still don't have a car)...
I still feel like I got kind of screwed over by not having those things, I never quite "learned" how to talk to people, so now that I'm in college for the second time, stuff like relationships feels even more hopeless, I feel so distant from everyone all the time (and hearing broken/sterilized people online try and downplay all of it by saying "Oh, that stuff's not necessary, it's only because the culture tries to push these things..." pisses me off to an irrational degree), but the only thing I really can do is keep moving forward despite all that.