Am I at fault or is he? Please read?

The situation is ludicrous to be quite honest! Giving him a ride is one thing, helping someone out. Doing a friend a favor is how I look at that. But then he brings someone that he knows you have issues with too. He is definitely in the wrong. He's lucky you are a non confrontational person (don't take that the wrong way, but not saying anything to him when he showed up with that girl goes to show you must be at least a little non confrontational), I would've left both of them on the side of the road. Ignore his silly threats, he sounds like an immature child. I wouldn't waste my breath if I was you. He deserves a swift kick in the ***, if it comes down to it and he still won't leave you alone get a restraining order, the only person that would embarr is him!