Mac, I had exactly the same problem, and what actually changed it for me was how I used my thoughts to distinguish perception. For example, negative thinking styles are the worst thing to do, ie. are they looking at me; he bumped me on purpose; etc... but that is what we are telling ourselves, and those thoughts are not the facts.
What I did was to learn and write down all these thoughts I have, when I became aggressive in public. I looked at every single one, then I had an opposite thinking style, being the actual factual one, for example; walking through a crowded shopping centre and someone bumps me walking past! a) turn and abuse them for bumping me in a crowded shopping centre? b) there is a crowd, he may of been thinking of something/somewhere else other than what he was doing, maybe they had PTSD, maybe they just had a fight with someone they love, maybe it was just an accident! I forced myself into as many crowded places as I could, and put my skills to practice. Yes, I was a mess for a while afterwards, but I pushed myself hard and fast, not allowing myself to get much rest to think inbetween, and now I sit in packed stadiums, concerts, you name it, without issue, all because I go into them with these thinking styles in place, and I keep them on my mind the entire time. I did this is peek hour traffic, all across the board, until I learnt very quickly that my brain wasn't correct, and was giving me what PTSD wanted me to have, not what I wanted to have or listen too. Mind over matter 110%.
This is why I mentioned earlier that I approach things a little differently with those who have military training, and the reason why, is because simply any person who has done so, has learnt to find constant new boundaries and have been pushed far beyond what they though their mind and body could even tolerate, for example, find the biggest hill and where going up it, then when at the top your happy, impressed and excited that you did it, then you all go back down, walking, getting your breathe back, thinking its all over and your going to hit the showers, only to reach the bottom after climbing an enormous mountain, to be told to turn around and do it again. You think just beforehand you can't do it, but when your standing at the top again, you just realised you could and did do it.
This particular area of training is actually something positive to use towards treating PTSD.