What is the moral lesson behind "Caline" story ?

"Caline" by Kate Chopin?

Caline leaves her home and everything she knows looking for something...... the passengers on the train that stopped right outside her home piqued her curiosity. She leaves her home for the city and soon finds its excitement was NOT what she desired..... she desired the young man who sketched her picture. The desire she felt was womanhood and her first crush..... thus, the moral would be not to make hasty decisions based upon girlhood fancy.

Why she was crying beside her big ,yellow cistern ?What is her true intention about staying with the flagman's sister ?

At the recent end , it said "but the pleasant faced boy , who had made her picture that day UNDER THE MULBERRY TREE " . What can this statement features or foreshadows or reflects her feelings that moment ?