She has never deigned to and never learned to play roles, and because of this, in one sense, she has never completed adolescence. Answering in terms of growth and development, Jill has never risked losing her self by playing roles as has Dan. That is another way of again saying that Jill has not completed psychological adolescence. On the other hand, Dan has completed adolescence successfully. The answer to that question, in part, requires a distinction between adolescence and being on the threshold, on the brink, of adulthood.
Adolescence is a time of tryouts, a time when playing the as-if game is desirable and rewarding.
However, the real world of adulthood is not make-believe, is no trial run, is not just faking it. Adulthood is real. One is out in a real world where one must rely on one's own real inner supplies. A collection of roles to be played more or less well in no way constitutes inner supplies for survival. On the brink, the becoming adult suddenly is exposed.