How do you tell if your boyfriend is a cheat?

look at his underwear or see if he is acting different or strange towards you. This happen to me. After I think about it I feel stupid for staying with the guy after he told me she pulled him and got him undressed, i come to realize that its not the girls fault its his because he stuck his dick in her and yeah to tell you the truth it doesn't bother me anymore. I'm done and over it or I should say him. He started lying about things and he started drinking more and smoking weed. He started getting abusive when i became pregnant with his baby and which i lost and he has no care in the world. But now I moved on and I'm much happier with a new guy who treats me like a queen and respects me for me. You could do the same.