Vronsky's mother, Countess Vronsky, is a society woman who was morally loose in her youth. She, like Princess Betsy, is a character who represents society's hypocrisy.
When we first meet her, Countess Vronsky says she has fallen in love with Anna. This is, of course, while Anna is peacefully married to Karenin, a high-up official, and seems on top of the world. But by the end of the novel, Countess Vronsky has only the vilest comments about Anna's death. Countess Vronsky is egotistical, self-serving, and ambitious.