I believe, that for those who really think that they are hikikomoris or are scared that they might be, the biggest factor in this whole shit is the fear of going down, further and further and not being able to get a grip and come out again.
I'm living like a shut-in for about 4 years+ and if I think back, it wasn't as bad in the beginning as it is now, it just constanty became worse.

Even now and back then I desperately thought, how to get out of this, cause I've got friggin' enough of being so darn lonely. It's not that I don't want friends or social contacts, it's just that I'm scared(don't even know exactly of what), I've gradually lost the lust for life and I'm probably way too easily or too much addicted to mangas, animes, dramas, virtual mprg(like fiesta) and fantasy stories in general. <-- withdrawal of reality and therefore society

call it hikikomori, shut-in, cocooning, idiot or psycho, whatever you want... just know that ppl like us suffer and don't really want to live this way
if it was so easy to become normal again, guess what we'd have done since a looong time ago??