I relate to the descriptions of it 100%, it kind of blew my mind when I heard it first. 

Is it a real thing, and if so, is there a specific subreddit for it, or is this the best community?

I don't really have external outbursts and abandonment issues (I'd like to be abandoned actually, as most of my pain is because of being too attached to my loved ones) and the kind of symptoms that are the most talked about here