Cheating definitely costs money. Someone having an affair will have to spend extra money on gas to meet with their secret lover. They will have to pay for meals. Expenses include hotels, rooms, incidental expenses, gifts, alcohol and more. In most situations a family’s budget simply did not plan for an affair. This creates an additional financial strain. To hide away from getting caught, it’s likely that your spouse will start paying cash for all of these items. The result is an excess of cash purchases which can’t be accounted for. You may find that while reviewing your bank statements, there is a decrease in the number of debit card / credit card purchases but an increase in ATM or counter withdrawals. Also to hide suspicion, your spouse may choose to use cash all the time – so that you can’t identify the suspicious purchases.