I think it's probably a fancy way of saying that at 16 she still didn't really understand love, or the fact that she was in love. At 16, that's a perfectly normal problem to have.This is cute and all, but their ages are a bit hard to reconcile with the story. Girl at 16 regards love as a "distant concept"? I know we're a few generations in the past, but... nah.
Hell, people still struggle to figure it out well into their senior years.