You can imagine that some in the royal court did not take kindly to the fact that she had the King’s ear. They were probably even more infuriated when she began working with the King’s sister Catherine to try and help ease the tensions between the Huguenots and the Catholics of the time. Catherine a Huguenot herself and Gabrielle a Catholic became a very powerful enforcers of the Kings edict of 1598 bestowing rights to the Huguenots.
Even with all the the political intrigue she bore the King three children from 1594 to 1598.
Divorce at the time wasn’t easy and The King was waiting for the Pope to annul his first marriage because Marguerite de Valois couldn’t have any children and also give him the right to remarry. Engaged to the King, Gabrielle was by then pregnant with their forth child, when suddenly suffered a seizure and died. There were rumors of poisoning at the time. Their forth child a son was still born.
The King was heart-broken and gave her a Queens funeral.
Never prejudge a work of art until you know the back story.