I have no idea where to put this but I figure this should be a decent section with logical thinkers. Background- My gf and I go to a party with my cousin, a good friend and a new friend who introduced us to the people at the party. Everything is going great minus some people being usually drunk but the group laughs them off and has a good time. We get ready to go and my cousin says, " your gf ran out the door". I find her and she is in tears, she tells me some guy hit on her and she turned him down saying she was with me. He tried dancing with her and once again got the cold shoulder, then he decided to grab her ass. That is when she left. I didn't see it because I was in the other room with a guy who was talking about how he set a trailer on fire so I was into the story and didn't see the situation happen. We all leave before the shock sets in. I flipped out by the time we got home and was ready to destroy this guy. My question is did I do the right thing by leaving with the gf and not beating the living piss out of this guy? I really wanted to beat this guy to death but the group said it was best to leave before I got mad so I did as they suggested.