As someone who has effectively deleted all of my (mainstream) social media accounts, I'd say that there a period between daily digital addiction and (never truly attainable) digital independence. One thing that helps is to go further and _delete_ the account, not just the app, because when we delete just the app, the account still lingers both online and in our minds. Our brains still have the muscle memory of the credentials (or the tools that lead to them, like a password manager or passkeys) used to log in again.
I deleted Facebook and Instagram a long time ago. I didn't just delete the app, I deleted the entire account. The only thing from Meta I still got (heavily against my will, if there's such a thing as "free will" when living within a deterministic cosmos) is WhatsApp, due to the fact that the country I live in (Brazil) uses it as a "super-(crappy-)app" as a replacement for most of the things that used to be done _in loco_ (in person).
In a nutshell, I deleted FB and IG, Twitter (soon after it became X), TikTok, Kwai (Kuaishou), Reddit, Telegram, Signal, YouTube, I deactivated LinkedIn. I even deleted non-mainstream profiles, such as Lemmy. Nowadays, all the social profiles I still got in the Web are Pixelfed, Bluesky, Mastodon (haven't been using it) and Friendica (idem), which I'm on the verge of deleting, too. I intend to focus more on Geminispace, but sometimes I also think about leaving it, out of a nihilistic sense that has been dominating me for a long time.
Yeah, it's extremely lonely. I mean, you nailed it: all social media can offer is parasocial relationships, which aren't human relationships (although I'm not sure what the definition of "human relationship" is, since my entire existence orbited like a Danse Macabre between peaceful solitude and suicidally-desperating loneliness, with myself having an avoidant personality with a tendency to not fit anywhere).
So loneliness isn't something emerged from the abandonment of social media: loneliness has always been there, just disguised as RGB pixels of illusory companionship. Sometimes people got their "real" (flesh and blood) "friends" added as contacts: this ends up tearing them apart (even decades-long friendships can be destroyed in mere minutes due to some online activity or inactivity).
In my case, to make things worse, there's this nihilistic sense that everything is devoid of purpose, which leads to an ever-increasing anhedonia. What was once joyful becomes boring, and even waking up and eating become an annoying routine. The current state of the world has been bleaker than ever, something, I guess, related to the COVID-19 pandemics (at least, for me, personally, it was such a traumatic part of my entire existence, more than being targeted by bullying back in the school).
How can one be simultaneously so miserably tired and constantly entertained?
Deep down, it sounds like everyone has the nihilistic spark, just incubated, waiting for the opportunity to accidentally look into the abyss (and when you look into the abyss, the abyss looks back). We usually don't look because we are too busy with mundane things: work, studies, hobbies, relationships, love/passion, family, projects... or social network doomscrooling/parasocial. All of these, deep down, are ways of avoiding looking into the abyss. So I would say that the answer to your question would be this: humans are tired of the Sisyphean effort, but entertaining the mind is an analgesic that allows Sisyphus to be happy ("one must imagine Sisyphus happy").
My brain grows as processed as the corner deli's slab of ham, but how else would I have discovered Smooth by Santana, which I listen to as I write?
I have discovered many things through parasocial relationships. Books, films, music, philosophers and thinkers, deities and mythologies... In part because (almost) everything we have learned and known has been communicated to us through other living beings (my parenthetical "almost" is a nod to self-acquired gnosis and supernatural phenomena such as automatic writing, but metaphysical forces are a kind of "being" too).
Do I have any other choice?
My nihilistic worldview would say that there's no such thing as a choice for matter-trapped beings, for everything we do is hardwired to physical and metaphysical processes (from biological instincts to a broad cosmic machinery, going through social compliance as perfectly shown by Derren Brown, as well as metaphysical influences from Archons which, IMO, are the only ones to possess "free will"). But I digress.
I'd say, within the mundane play-script (where "to be or not to be" is a question), we could try to stick to a digital minimalism, exploring places like here, the Geminispace. People are more human over here.