Girl

I assume the person giving the girl all the advice is her mother. It seems that she is speaking from an either lower class or middle class perspective. More than likely she's middle class and sees herself as upper-class, or likes to see herself as upper-class; this explains her hatred toward lower class. She seems to have some good advice against becoming a slut; maybe she was one, or acted like one and attributes her former behaviors to her current middle or lower class status.

She's living through her daughter's future and being ever so careful to tell her to do all the things she wishes she had done in order to obtain higher class status. She's also telling her not to do some of the things she did that ruined her chances with the upper class men. She tells her how to make the medicine that prevents children before they become children; if only she had known about this medicine when she was impregnated by a lower class scoundrel. All that matters now is that her daughter knows, and if she makes the same mistake it won't be the end of her upper class dreams.