Disconnect
Has your spouse been avoiding you lately? Do you feel that there is a decrease of sexual interest in you? Has the marriage become almost too routine? Have those lately night heart to heart talks come to an end? This emotional and physical disconnect could be a sign that your spouse is feeling guilty about having an affair. He could be distancing himself from you to relieve the guilt. When you ask what is wrong, your spouse might get defensive. In a healthy marriage, a spouse is usually willing to talk things over. However, if your spouse is having an affair, he might refuse to talk about the problems even though it might be clear that something is troubling him. Sometimes your spouse might try to avoid you entirely. Obviously, be on the lookout for new and unusual work hours. Is your spouse coming back late from work? Are there slightly more meetings than usual? Are there suddenly travel related work trips?
Money Trail
Are their unexplained expenses on the credit cards? Remember how much your spouse has spent on you. If he or she has a new lover, the money meant for you is going toward someone else. Check the cell phone bill. Are there added charges? In addition, most cell phone bills keep a call log. Check for suspicious and new numbers. Check the joint bank account. See if there are any interesting withdrawals?
Appearance
Look for changes in physical appearance. Has your spouse brought newer clothes? For women, has she started wearing more makeup? For men, has he starting wear cologne? Are there suddenly visits to the gym without warning? Figure out the reason for this change. Is your spouse trying to impress you? Or is he/she trying to impress someone else?
New smells. You nose becomes accustomed to smells that are encountered on a regular basis. (This is why it is really hard for most people to notice their own body odor.) If you're spouse is seeing a new lover, he or she might pick up new smells. Because these smells are new to your nose, you should immediately notice something might be wrong. Also keep in mind that your spouse can be adding new smells to hide other smells. A cheating husband can spray himself with cologne before entering the house toe cover up the smell of anther woman.
Technology
Has your spouse begun deleting the history on his computer? When you look at his phone, do you realize that call and text message logs are suddenly not being saved? Or maybe your spouse has been on the computer a lot more. Does he/she stay on the computer after you go to bed? If so, your spouse might be using the time to communicate with his lover. Is there a sudden appreance of a web cam? Your spouse can be using it to communicate with his new lover.