So sometimes the two get confused in my head.
This isn't true for people on my own FL 'cause them I've spoken to personally, on occasion and often frequently, nor of anyone I've met in the flesh, and generally not true of the more mundane sort of lj user, esp the sort who records their twitters. It takes a certain level of (possibly deliberate) personal style for the fuzzing to begin. But I was reading another Aubrey/ Maturin the other day, and considering Stephen (who still looks to me like Wen Zhong with a big nose, though with an Irish father Stephen might in fact *not* have had one of those honking French or English nebs the French or English are so prone to sporting) and realized that in fact I think of, oh say bravecows in exactly the same way as I think of Stephen Maturin. They have a similar degree of reality in my mind. This is par for the course with a really well-conceived fictional character- Stephen and Wen Zhong both seem 'real.' New to me, though, is the phenomenon of a real person who feels like a literary character, simply because one meets them in a non-personal print context.
incandescens would probably still feel like a character in a book if I hadn't actually corresponded with her; several people I won't name still do because I never have. (One of them, found years back by following links, inhabits an on-going novel, with a wealthy old-money family background, eccentric relatives, ex-same-sex lovers, a marriage that happened and fell apart pretty much in the course of the lj, a current long distance relationship between two continents, and so on.) Only the fact that I once met petronia makes her real, in the face of determined and convincing efforts by her lj to render her fictional.
Not sure what ramifications this has. RL-wise, none: it's purely a matter of perceived Net reality. But possibly I could make the reality gap work to diminish the annoyance factor of those lj personalities who by reflex, and regularly, turn me into my mother (How can anyone be so STUPID?!)-- and who are inescapable because everyone else has them friended, for reasons I, naturally, can't begin to understand. Why would anyone want Wu Zi Xu on their FL? Not that Wu Zi Xu is a good example, because in fact I hate that quite fictitious creation far more directly and personally than I do, say, the various Internet Aunties whose full-fed self-approbation (or demagogic tendencies, whichever) are the bane of my FFL's reading existence. But think of them as having no more real existence than oily Wang Sun Luos or morally shabby Gong Sun Xiongs- disgusting, but not something that actually affects me- and I can begin to live with them.
Common wisdom then is wrong. That's not a living breathing human being there; it's a character in one of the nastier of Kingsley Amis' novels, and hence dismissable.