She and her hsuband have used his ill-gotten gains from bogus lawsuits tobuild a big house in the country; since she may not live long enough to actually see him get elected, she needs to build a legacy now. The living children seem to be trophy kids, who are brought out for photo opps when convenient.
Contrawise, the focus on death, on risk -- the extreme risk of Presidential politics, the mind-tricking focus during the crafting of fund-raising campaigns ... these are negatives.
Is Elizabeth looking to be the sacrifice? That by her death her husband gets a sympathy vote into office? That is both reckless and dishonorable.
Their duty is to the living, their living children.