Who is Lady Robsart from The Virgin's Lover and what is their importance?

The Lady Robsart, Amy's stepmother and wife to Lord Robsart, is the matriarch of a lesser known family from Norfolk who has done well through hard work and sacrifice. The Robsarts are presented as a somewhat simple family who believe in hard work and the solid application of good sense: not trusting the appearance, fame and glamor of court but preferring to rise in their own way through labor and production on their farms and estates. The Robsarts had apparently been considered a poor match for the Dudleys by both sides of the marriage of Amy and Robert, but the young couple had been in love. The differences, however, in the respective upbringing and outlook of Amy and Robert begins to show itself through the course of this book and become insurmountable.