Peg is a woman that lives for titles.
Independent
Feminist
Humanitarian
Self made
Duchess
Princess
The titles in one world are Royal and aristocratic, the other "titles" when constantly put forward for self aggrandization are having the same purpose.
In addition to being titled in Pegs case meant diplomatic treatment, motorcade, and mingling with the biggest both financially and political.
I don't think that she was told by a aristo lady anything, the aristos close ranks, and live for the Status quo.
If anything happened, it was behind her back. But she believed in the popularity contest, Diana won it against Charles.