The moment Connie grows up in Oates' "Where Are You Going, Where Have You Been?" is when she is confronted with the sense that she is trapped and realizes exactly what lies ahead of her: death at the hands of Arnold Friend.
Up until now, Connie has been a fifteen-year-old with little faith in her mother's intelligence, and little confidence in her mother's advice or the guidelines her mom has tried to impose in Connie's life for her own good. That is not to say Connie deserves to be punished at the hands of Arnold Friend: everyone makes mistakes and thankfully, most have the opportunity to not only survive them, but also to have plenty of time to accept or reject the knowledge that comes from making the mistake. Connie's life-lesson here will be her last, and I believe that is the moment that life comes into complete focus for her—providing instant and brilliant clarity. An inkling of this change begins just after she screams into the phone with no result—she must be feeling complete frustration because she is trapped: Arnold has told her that if she doesn't comply with his demands (delivered like requests with his kindly incantations), he will also "hurt" all of her family members. He asks...
"You don't want your people in any trouble, do you?"
Suddenly, she begins to see the truth of her situation—beyond this moment...past the "inkling."
She was hollow with what had been fear, but what was now just an emptiness. All that screaming had blasted it out of her. She sat, one leg cramped under her, and deep inside her brain was something like a pinpoint of light that kept going and would not let her relax. I'm not going to see my mother again. She thought, I'm not going to sleep in my bed again...
Under other circumstances, it almost sounds like something a bride might reflect upon the night before her wedding: that things with her parents wouldn't be the same anymore, and that she wouldn't ever sleep in her bed again. If that were the case, it would be a rite of passage. However, in this situation, she is leaving the things of childhood behind...but not for a new life. This, then, is the moment Connie grows up.
Her thinking changes dramatically and she sees the world very much like an old soul approaching death:
She felt her pounding heart. Her hand seemed to enclose it. She thought for the first time in her life that it was nothing that was hers, that belonged to her, but just a pounding, living thing inside this body that wasn't hers either.
This sounds very much like coming to terms with a hard lesson—which is very much the case with Connie, but it comes at too great a price.