Well, you all are just perfect little Mommies.
Each one of you that say you have no sympathy for this girl admit you had a mother close by who relieved you on occasion. Yes, you were the primary caregiver but you weren't completely alone. At least you had someone to talk to when the going got tough.
I don't know this girl's situation - whether she had family nearby or not - but I remember quite well being completely alone, half a continent away from my family, with a crying infant.
I'm not offering any excuses or suggesting she should not be punished, but I do understand what prompted her to do it.