My top pick for tips on how to catch cheating is this book by Sarah Paul

Can You Recognize the Signs of a Cheating Girlfriend?

While statistics on infidelity tell us that men are the main culprits for cheating, the fact is that women are just as guilty of cheating as men. Women seems to be more devious in being able to keep their affairs secret, so much so that their best friends don’t even know about it. Although it is harder to spot the signs of a cheating girlfriend they are there. You just have to learn what they are so you can recognize them.

It is true that all women like to wear sexy lingerie to make them feel attractive and to turn on their partner. When you notice that your girlfriend still wears her sexy lingerie but doesn’t want to show it to you or displays little interest in lovemaking with you, then you should go with your feeling that she may be cheating. You should bring up the subject, just to see what she says because it is possible there may be a reasonable explanation, such as being tired or not feeling well.

A “sudden” interest in dressing up, a change in hairstyle or hair color, or a change in perfume could also be a sign of cheating. This is not to say that every time your girlfriend buys a new outfit or changes her hairstyle, she is cheating. The operative word here is “Sudden” in that she seems obsessed in making sure that she looks and smells nice every time she leaves the house. This is especially true if the changes make her seem more provocative and you hadn’t given any hints or suggestions that it would be something you would like her to do.

Intimacy and emotional attachment are two things that women equate as being synonymous. If you walked hand in hand or hugged and kissed a lot and now she doesn’t seem to want to do this, it could be a sign that she is losing interest in you and has someone else in her life.

Depending on the nature of her job, she may have to work overtime on occasion or travel. If this activity has suddenly increased and she is working lots of extra hours, you should be inquisitive to find out how much extra money she is earning. If there is no noticeable difference in her pay, then it is very likely that the overtime hours are not being spent in the workplace. A drastic increase in travel, especially to the same locations, could also tell you that she is taking trips with someone else or that she met someone on one of her business trips and keeps going back to see him.

There is no one sign that can attribute to your girlfriend cheating on you. One or two of these signs can arouse your suspicions so that you start noticing little things that didn’t appear significant in the past. One of these is to notice how she acts when talking on the cell phone. When she openly talks on the phone in front of you at certain times, but moves to another room when she receives some of the calls, this caller could be another man that she doesn’t want you to know about.