If your spouse is cheating, he/she is not likely to admit it. The more you accuse, the more they will deny.

I believe you have a right to know what is going on. I would encourage you to make a note of all the evidence that leads you to conclude he/she is involved in an affair. (See the "Signs of an Affair" list below.) It's unlikely that a single indicator will be absolute proof that something is going on, but any pattern of changed behavior, along with your gut suspicions, are important to consider. You should take time to gather as much information as you can before talking to your spouse about it.

Ideally, you should remain in control of yourself when you question your spouse. If you are likely to lose your temper, you may want to consider writing letter and asking your spouse to read it alone or with you nearby. If there is any chance that they might come clean (a possibility if the affair has run its course of if they are struggling with a weight of guilt), you are more likely to achieve a desired result with controlled confrontation rather than with angry accusations. Anger puts people into a "fight or flight" mode that prohibits healthy dialogue. Don't assume; don't blame; just ask. But don't give them all the evidence you have. Be sure to hold out some important information because this will be a good indicator of how honest they are willing to be. If they try to create a story to explain away your evidence, it's likely that your withheld information will make their continued deception obvious.

In most cases, the spouse will deny an affair and will likely try to make you feel ridiculous for even suspecting such a thing. Listen; don't argue. Make sure you have clearly communicated your questions and concerns and let them respond. Do the answers make sense? Is there a chance you got things wrong?

If you still have any doubt, you have the right to know the truth. You may want to wait and try again to present your spouse with troubling observations, but at some point, you may need to take more deliberate steps to find out the truth. See the entry Trying to Catch Your Spouse in an Affair for more information.

The Signs of an Affair: a change in their sexual behavior with you (less sex, or suddenly trying new things); an unexplained sexually transmitted disease; being overly-defensive about the person you suspect; unaccounted for time away from you; unusual changes in personal or work schedules; increased emotional distance from you and other family members; the sense that their thoughts are often "somewhere else"; unexplained expenses; sudden interest in new activities or hobbies; heightened attention to appearance (buying new clothes, getting in shape); secrecy with phone calls, emails, or text messages; the smell of someone else's perfume or cologne; being freshly showered at odd times of the day/night; being vague about where they were or who they were with... speaking in generalities and avoiding specifics.