What's cheating to you?

The worst is emotional cheating... My G-d brother ended up in a onesided emotional relationship with a girl who had a man she was fuccing. They had classes together and ol' girl would talk to my G-d brother all the time about ish--including her relationship. The kicker was my G-d brother wasn't feeling this girl like she was feeling him and thought they were just friends. They continued talking about dumb ish at school and on the phone...BUT when... he started dating someone. Ol' girl from his class who had a MAN that she was FUCCING found out--she turned into that chick from fatal attraction and caused a scene at my G-d brother's school. Her boyfriend and my G-d brother were like WTF...