The Price of a Broken Heart (1999)

Fact-based story about a landmark legal battle. A woman (Park Overall) learns that her husband has been having a very open affair with his secretary (Laura Innes) and has promised marriage. The wife sues for divorce and also sues the secretary based on an obscure law on alienation of affection, which was created to protect married couples from homewreckers. This sets a new court room consideration, as the culpability of the other woman must be defended and removes from consideration the fault of the married partners.