Online friends

Yeah, what’s up with that? Is it something about not seeing the person face to face that makes us so prone to opening up in this way? The absence of normal social pretense maybe?

People keep their defenses up more when they have to do "facework". If you're not having to make eye contact, it's easier to speak freely.
Even though it's rare these days, it's the reason behind that whole Freudian idea of therapy where the patient lies on the couch and isn't looking at the clinician.
- In fairness, Freud also advocating giving the patient cocaine to open them up. Tho he's not entirely wrong....
- True, and there are other reasons too.
  Knowing someone (only) online means they probably don't intersect with your in-person friends, colleagues and family, and so what you say stays compartmentalised rather than leaking into the rest of your life. This means you're more willing to take conversational risks and be authentic, because it can't affect your other personal or professional relationships.
- I had no idea that came from Freud! What a mixed bag of a guy.
I feel like it's a combination of anonymity making you invincible: If the other person attacks you with the infos you've given them, you just close the chat window and continue with your life.
...and anonymity stopping others from helping you: If you open up to someone, there's an implicit expectation that they should try to help you, if they're not an asshole. But many people don't actually want help, because they don't want to be a burden. They just want someone to listen.
So, you either open up to an asshole (which is how many, traditionally mostly male friendships function), or you open up to some trapped behind a glass screen.

The weirdest part for me is feeling totally comfortable talking on screen about anything, but then when you think about meeting in person, being worried that you won't have anything to talk about and it'll be awkward.

I found the whole experience liberating.

My favorite is when you've been online friends with someone for 10 years, talk for hours nearly everyday, confide in them, think of them as someone important to you only for them to say "you're only text on a screen to me" and then ghost you for 2 years after a mild argument.

I think you met a psychopath

I spent 8 hours a day for 2 years chatting with my WoW guildies. Never learned their names.

There is a weird catharsis to dumping normally very privileged information on people somewhat anonymously. Like, nothing identifiable, but I'm not gonna casually drop that I received a heart transplant on people IRL with the ease that I can do it here. You don't have to pretend to care if you don't want to, unlike in person where I get the "Oh, what do I say about that?" face.