What is the main conflict in Wide Sargasso Sea by Jean Rhys?

The unique novel seeks to recreate the true story of Bertha Mason, the Jamaican mad wife of Edward Rochester in Charlotte Bronte's Jane Eyre. In telling Bertha's story (known in Wide Sargasso Sea as Antoinette Cosway), Rhys explores the complex relations between white and black West Indians, and between the old slaveholding West Indian families and the new English settlers in the post-emancipation Caribbean. Set mainly in Jamaica and Dominica, the country of Rhys's birth, the novel describes how Antoinette became mad. In Bronte's novel, Bertha/Antoinette is a monster, described as violent, insane, and promiscuous.