The "infidelity" part of Cherry's comments make this one tough because the infidelity in this era seems like the most egregious. But if infidelity is off the table, it makes us highly suspicious of Beth Ann's neighbour, Sheila (Alicia Coppola). She's a scene-stealer right from the start and that makes her a great suspect.
But who does she kill? We're going out on a limb and saying Sheila will kill Beth Ann's husband. Not necessarily because of the cheating, but more so because she thinks she is rescuing Beth Ann from a horrible situation.
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