Jacky Bast - Prostitute or Floozy?

While I'm no Dr Henry Higgins by any means I think a lot can be devolved from the characters' dialects. The social classes of immediately post Victorian England are portrayed wonderfully in this film.
The Wilcox' are aristocrats, old money. Obviously under Henry's shrewd direction the money pot isn't getting any smaller either. The family speaks in the upper class tones, wording assembled in the manner made familiar in the recorded speeches of Winston Churchill.
The Schlegels are middle class, though the term meant a higher standing than we apply it in our familiar use. They don't 'work' (heavens!) but appear to subsist on an annuity or trust, and they have a servant. Not a lavish existence but a very comfortable one. They speak in a cultured manner too.
The Basts are different. Leonard's manner of speech is not as completely refined as the Schlegels but perfectly acceptable in their company.
Jacky Bast on the other hand, speaks (at least to my ear) Cockney. (Maybe the directors went a bit over the top on that one) She's obviously not on the same plane as her husband and though she adores him, she doesn't understand him at all. While he wants to explore the intricacies of literature she wants to frolic. When Leonard is studying the stars all she has thoughts for is to get him back inside.
Bast is an interesting study. He is cultured and intellegent and yet dwells in the working class. Was his family of higher station and fallen on harder times? Is he a 'second son' and the rules of Primogeniture left him without inheritance or a remittance?
Did he indeed find the lush young Jacky, and try to elevate her from her former place? (though she's still a Cockney at heart)
I wouldn't put too much effort into labeling Jacky. She's just trying to hold on to what she has, using the only lure she possesses.