One reason for the increased popularity of expensive engagement rings is its relationship to human sexuality and the woman’s marriage prospects. Until the Great Depression, a man who broke off a marriage engagement could be sued for breach of promise.
Monetary damages included actual expenses incurred in preparing for the wedding, plus damages for emotional distress and loss of other marriage prospects. Damages were greatly increased if the woman had engaged in sexual intercourse with her fiancé. Beginning in 1935, these laws were repealed or limited. However, the social and financial cost of a broken engagement was no less: marriage was the only financially sound option for most women, and if she was no longer a virgin, her prospects for a suitable future marriage were greatly decreased. The diamond engagement ring thus became a source of financial security for the woman