In the last year or so, I've noticed a lot of people asking this question:
"How do I know if my girlfriend is cheating on me?"
Before we answer that question https://cheatingbuster.com/cheating-girlfriend/, let's take a step back and see why people ask it in the first place.
There are many different ways to know if your girlfriend is cheating on you. The thing is, every time someone asks me, "How do I know if my girlfriend is cheating on me?" they're looking for the easy way out of their problems or they want to say something they don't want to admit to themselves because it seems too personal, embarrassing or difficult... But they can't bring themselves to admit it because they think there's some magic test that will tell you when your girlfriend is cheating on you or something (finally, admitting "it's just sex" sounds like an excuse).
The truth is, it doesn't matter how you determine when your girlfriend is cheating on you - what matters is how well you do it. How well do you catch her in the act? How well do you arrest her? How well do you get the evidence? Yes, there are ways to know if your girlfriend cheated on you, but there really are no magic tests for cheating. And even if there were, everyone will use them in their own way, so most of them will fail at least a few times (and sometimes fail completely).
So why should anyone care about what testing might reveal after all when a person wants to change, it's unclear exactly what they want to do.