I thought that she left Quilty after a short time because of his lifestyle with another girl. I think that I read that she did not meet her husband until later. Perhaps her husband was her desire to leave her sordid past and live a somewhat respectable life. She did not want him to know the truth about Humbert, just that he was her father. She even made the comment that she supposed he was a good father in his own way. This may have been in reference to the ways in which he tried to make her happy so that he would not lose her. She still saw herself as being partially or equally responsible.
I think leaving Humbert was something she thought about often. I think the way her character is just revealed in small slivers of Humbert's thoughts, almost by accident reveals more than it hides. He did not really want to admit that she was unhappy, than she never got any pleasure from sex, that she was a prisoner, that he took away her life.
Lolita did have a rebelious nature, and her mother's view of her as being a 'bad' child probably fed into her view of herself. She had a survivalist's instinct and she learned to manipulate Humbert. There are several comments about her thinking he murdered her mother. She really never knew exactly what happened to her mother and she really had no one else to turn to except Humbert.