How do you know if someone cheating on you when your not home an at work ? An how do you know a person is cheating in general?

When my ex started cheating on me, she began visibly distancing herself. Both emotionally and physically. We began spending less time together, and when i asked why there was always some obvious excuse. She also began emotionally pushing me away, got cranky more then usual and gave no reason for it etc. I began suspecting that something was up, but i was in Afghanistan at the time, so i put off confronting her and asking what was going on until i got back. Then i go leave during Easter, and i wanted to spend some time with her when i got home. She refused saying that she already had plans to spend the weekend with her father, knowing that her father and i did not get along. I got angry at that, to which she blurred out that she feels like i am in the way of her happiness, and broke off contact. A few days later i found out through a mutual friend that she had not spent the whole weekend with her father as she had told me, but with some guy friend she met in a bus about a month ago. And that she had been spending every weekend with that guy for over a month now.

Did not take a genius to figure out what was actually going on.

You have to investigate!