My sister went out with this guy, let's say his name is "GREG". She was really serious with Greg and her best friend knew it too. Life happened, my sister and Greg broke up but were still strong in feelings with each other. Well, her best friend married a guy for 2 years in AZ. Once she came back to visit, we all hung out in a group together, including Greg and all. Well, my sister caught her best friend kissing Greg and stormed out of the house and left. When I walked in, they were just acting like nothing happened. Her friend was married and kissed this guy! Anyway, after that incident, she left back to AZ and decided to divorce her husband. I asked her why and she said cause she doesn't love him anymore. Not so long afterwards, she hooked up with Greg(the guy she cheated on her husband with). My sister is still pretty pissed about this, but her friend is saying not to be. Is she worth being friends with or should she be considered the other B word?