I don't know her, but I have seen Rec. sluts come and go. They use men for toys just like some for money or drugs. If this is the case, I might just see if I can keep her on tap to scratch an itch from time to time. But, she is certainly not worth any emotional attachement...oh don't forget to hide the video camera...snicker...might come in handy...
Almost certainly don't kick his ***. outcome 1: He actually beats yours *** and you get no respect from the girl. outcome 2: You beat his *** and you get no respect from the girl. outcome 3: You really F*** his sh*t up and you go to jail for a felony and you lose your job and everything while the girl laughs her *** off. There is no scenario that a fight will gain you anything but there is a lot to lose...over apparently nothing...Is she worth that? I guess that is up to you.
About the crew...They certainly get chicken sh*t points, but not necessarily azzhole points. Given the option of going riding and keep their mouth shut or entering into the fray, the easiest is certainly the former and not the latter. My guess is that they probably feel bad, but if they just say dude I wanted to go riding...I would say get some friends with a bit more character...this might be tough at your age when fun often out ranks character.
Karl