Bad Neighbors — K.K. Beck

Anita and David Jamison are having a hard time. Anita is bitter that David is a slacker househusband while she works hard to earn the family's only income. David feels undervalued by his wife and is frustrated with his failed advertising career. With one income, a hefty mortgage on an old house, two kids, and a lagging sex life, Anita and David's marriage is more than a little strained. Now they also have a new nosey neighbor, Sue, who makes domestic life appear effortless.
Family matters for the Jamisons go from bad to worse as Anita starts to seek comfort in another man's arms and David starts to accept household help from overly attentive Sue, who is more and more involved in the Jamison household.