Rise above the anger? WWJD?

I'm incredibly, insanely upset at a former "friend" and I am struggling very much with the most un-Christian thoughts one can have about this person. My first impulse is to wring her neck, my second is to call and scream at her, and my third is to write her a letter explaining where I think our friendship has gone wrong, what I think she needs to change, and my hopes that one day she won't be a "liar and cheat." But I think it would get tossed. Trust me, there has already been a letter for me just to emotionally "vomit" all this onto paper, that letter I would never send as it is the MOST un-Christ Like thing I've ever written.

Basically this "friend" begged me to intro her and her husband to my parents so he could do a bunch of contracting work for them. They flaked. BIG TIME. My parents are out a LOT of money and are about to have a lien put on their house by a subcontractor this "friend" used and hasn't paid. My parents are a bit upset with me for introducing them and I'm SUPER upset at at these "friends" for being incredible liars and flakes.

So does anyone have any soothing messages to calm my un-Christ Like anger? I just keep chanting "Love one another" because it sounds better than, "let's go wring her scrawny neck!" and I don't want to have to repent of too many bad words. Seriously, what an awful thing to do.

Also, her husband used a fraudulent credit card to pay the subcontractor at one time and this subcontractor is going to send the info to the police so my friend's husband may be arrested, so I really am trying to find it in me to pray for their family because tough times are ahead for them as on top of all that my parents are meeting with an attorney to file a lawsuit rather than going the small claims route.