Relatioships are a weird thing. Sometimes you can marry someone and not really care about them at all. Sometimes you can want someone so much you will go to ridiculous lengths to murder their current spouse using the good old US MAIL!
Grace tells us the story of Cordelia Botkin who hatched a pretty great plan except since there was no TV in 1898 so she had not learned about how covering ones tracks is pretty important when committing crimes.
We have poison hearts, poison candy, and lots of infidelity in this story, and what more could you want?