I think this has to do with her being really frozen in that state. Her psychological development as well as her body. No puberty, no adolescence, no problem!cmfireflies wrote:she found Oskar.
Also, centuries of loneliness didn't turn Eli into a whiny emo or an uncaring monster.
It is true that she can feel the fear of a psychological death (AKA loneliness) but this goes with any age from childhood to adulthood. So this is pretty much common to all of us.
I think this is where we can envy Eli. She didn't progress from being a child mentally and physically. Well, the envy is from us adults. From a child's point of view, I assume someone like Eli and Oskar, they envy the adults because we have this sense of "control" over our circumstances and environment. But well, as you and I know it, there isn't much to control at this end as well.