When you try to contact your partner when they are out, your partner may send your call to voicemail or not return your text messages. Your partner may frequently say, “I didn’t hear the phone. " or “Sorry, my battery died. " Note whether this is a consistent pattern, or whether it lasts only a short time. Your partner may well have a project at work taking up more of their time. However, they should feel comfortable telling you that this is what’s happening. If not, this could be a sign that your partner is cheating.

Make sure the secretiveness is something new. If your partner has always been private, it may be more difficult for you to notice anything. If you ask your partner who was on the phone or what they were doing on the computer, your partner may respond by saying, “No one,” or “It’s work related. " or “Wrong number. " or “Why are you asking?"[2] X Research source

During arguments, your partner may try to make it seem like you are the problem in the relationship instead of them. [4] X Research source Remember that your partner is acting this way because of the lie that they are living. You should not feel guilty about anything.

An increase in your partner’s sex drive or an interest in trying different sexual things may also be a clue. If you tell your partner that you have noticed a difference, they will probably deny it or suggest that you are being sensitive or unreasonable.

Notice if your partner smells differently when they come home as well.

You can also check email, Facebook, or Twitter. See if there has been any contact with new people. If you have access to their computer, check the web browsing history as well. Check their phone for dating apps (e. g. , Tinder, OkCupid, Plenty of Fish, etc. ) as well. These could be used to meet other people. If your partner deletes their call log, you can get call records from the phone carrier. Going through your partner’s phone is an invasion of privacy. If your partner is not cheating, they may feel betrayed by your lack of trust.

PIs can be found by searching Google or the Yellow Pages, or by getting a referral from a friend or the local police department. Find a PI that is licensed with your state. Speak with a few PIs before you make your choice. You want someone who is experienced and has a good reviews. Hire an investigator that specializes in infidelity investigations.

Hardware keyloggers work for desktops and laptops with an external keyboard. These devices are plugged into the back of the computer. Check to see if the computer has a USB socket or a PS/2 Socket and then buy the appropriate keylogger. You can get a keylogger with 2GB of storage space for about $10. If you plan on checking the data daily, this should be sufficient. Additional storage space will cost more money. These devices will be visible to your partner if they are observant. Software keyloggers have the ability to save passwords, save and log instant messenger conversations, and take screenshots at set times. More advanced software keyloggers can email you information as well. Software keyloggers can be purchased online. [9] X Research source Be prepared to pay at least $40. Be careful with free keylogger downloads. Most of this software is not free and is actually used to monitor your keystrokes.

This software can cost anywhere between $70 and $300, but it is a good investment. If your partner’s phone is locked, you will need the pass code. Keep in mind that spying on someone’s cell phone is illegal in some states. Check your local laws before you do this.

Do not wear any ridiculous disguises. You do not want to draw any attention to yourself. Take binoculars with you so you can see what your partner is doing from far away. Use the mirrors of your car to watch your partner instead of staring directly at them.

Do not go back and read what you wrote. Burn the letter when you are finished writing. This exercise will allow you to get all of your feelings out in a safe way.

Set a time limit for the conversation. Two hours is a reasonable amount of time to start with. This conversation should begin when you are ready. Do not rush or force yourself to discuss this with your partner unless you want to. You will most likely need to have multiple conversations. One meeting may not be enough.