Even though infidelity is a centuries-old problem, monogamy is still an ideal that many couples strive for in their marriages. A 2012 study by the Associated Press reported that in 41 percent of marriages, one or both spouses admit to being either sexually or emotionally unfaithful. The quicker you can identify a cheating spouse, the faster you can resolve these issues in your marriage. Increasingly Argumentative: In her article, the "Warning Signs of Infidelity," Dr. Betty P