Hello! Im "the 21 yo with 18 yo friend who was worried"! I wanted to thank all of you for your advices and sharing your opinions. I looked up moral OCD and it seems to be the case when it comes to the first part of my last ask. I'll work on that. And I'm ace but I don't usually have problem talking about sexual topics, I think this was the result of OCD + how people call everyone things online.
Now the second part, about the self harm and suicide, I would say that those two events were the only times that they asked for help. And they later apologized for worrying me. They are better now. Realistically I know that I can't do much since I'm just an online friend, but I thought maybe I could do more. (I did suggest therapist but they had bad experience.) (I would like to know if there sources like books that I can read or suggest it to them? They haven't asked for more help and have promised me that they are fine, but just in case.)
About the independence, they have online friends other than me and they had irl friends too. Half way through our friendship their irl friends and them stopped being friends (not my friend's fault, and they weren't talking about this to me specifically. Their other online friends were also present). So the reason they refuse to make more friends now is mostly because the wound is fresh. Looking at my last ask I cut some some parts of it because I didn't want it to be long. But they aren't dependent on me mostly. I'm their closest friend but we do go days without talking. Sometimes I'm too busy or overwhelmed by social media and I respond late. They understand. I did have irl friends that were very dependent on me so I wanted to know if there are things that I can do to stop this going that way.(I don't think it will go that way, but still)
I'm actually way happier with them being my friend than before(they are too according to them). The friendship goes both ways. We both complain about things sometimes and they do listen to me as I listen to them. They also are not the type of person to force their opinions on me or force me to agree with them. The suggestive arts were sent in good faith. They enjoyed something and sent it to me thinking I would too (and I would have, but the moral OCD happend). We mostly talk about fandom things and I would say they don't fall under "anti" label! They also like it when I write analysis messages about fandoms.( I get talkative when it comes to fandom and they don't mind. They enjoy it even!) They also check in with me and have helped me too. I have a problem with drinking water and it's nice to see "hi! Did you drink water today?" message when I open the app (as an example).
I wrote my last ask when I was overwhelmed by OCD (I did know that I have OCD, but I didn't know moral OCD exist). I cut some parts and made it sound very bad, that is on me. I wanted to thank everyone again for sharing their advices and experiences. Especially for telling me to look up moral OCD beacuse that is life changing for me! I hope the best for all of you.
I'm sure people can suggest resources, but some of the best ones, as far as I know, are hotlines where a person can talk to a live human with some training. Which hotline a person should call depends on their geographical location. That's why you more often see advice about butting out and not taking on everyone else's problems around here. It's partly a response to cringeworthy authors' notes on fic that are like "Stay safe, guys! 1-800-must live in the US or fuck you".
It does sound like the issue may just be that you need to chill out. This type of OCD is surprisingly common around fandom, and the constant noise and paranoia about delicate minors and Think of the Children really exacerbates these tendencies if you have them. Scaling back on how much you look at alarmist social media posts instead of chill, positive things may help.