Willow's Flame - Stephanie Fields - Bog

So, what is it exactly that labels one a serial killer? Is it the amount of people that you kill, statistically speaking? What if the killing is within reason? Can the murder, or murders be justified? If the world is a better place without the people who are killed, is it really such a tragedy?
A serial killer is typically a person who murders three or more people, usually in service of abnormal psychological gratification, with the murders taking place over more than a month and including a significant period of time between them. - https://en.m.Wikipedia.org
In what would seem to be a cozy home in Chicago and a couple that had it all, Willow finds herself questioning the life she chose with her husband Neil. When his secrets begin to unfold, she gets caught up in a spicy affair with Brock, who she met at a book club. It turns out Neil isn't the only one bearing secrets. Pauleen, who's named The Nosey Neighbor hears it all through the thin walls and starts to connect the dots herself when poor, sweet Willow goes missing.