Every time someone passes me too close or pulls out in front of me I fantasise about chasing them down and confronting them. The once I did it i banged on the car before I saw who was driving and a tiny old woman was sat at the wheel. I said politely 'oh, you k just nearly ran me over' and she burst into tears, I was left at the traffic lights having to comfort the lady. Was I right to tell her, probably, was it satisfying, not at all
My mum's colleague was running on the beach recently when someone's young dog started trying to bite his trainers. When he asked the owner to call his dog he was calmly head-butted in the face.
I was in a bus a while back when the driver beeped his horn and the boy racer who'd cut him off slammed on his brakes and got out of car armed with a hammer.
My point, you don't know who you're dealing with. Is confronting someone going to make your feel better? I can't imagine you'd change anything in this situation. In the heat of the moment I agree it's hard not to react. By all means report to the police (I've been reading recently about prosecutions but these did come from helmet cams) but I urge you (and everyone else) to avoid confrontation at all costs, not because you're not in the right but because you have no idea which axe/gun/knife wielding maniac you're confronting. Car incidents are horrible and leave you shaken but report it and try not to think about it afterwards.
On a personal positive note I went on a course run by 'go smarter to work' which was really helpful in terms of road positioning and by not giving people the choice of overtaking in dangerous places by my road positioning I feel things have improved a bit.