I can't relate much because for some reason I was born easy-going. It's good that at least for today you can look within and take a look at anger when it knocks on your door. Resentment and anger is something alien to me for some reason. I dunno, I've just always been the complete opposite. My mother-in-law once told me early on that I was the most patient man she had ever met.
Do I get angry? Yes. I just have a veeeeeerrrryyyyy looooooong fuse. I figure that that no matter what, I have to keep my self centered. Like I'm the eye of the hurricane, remaining calm and peaceful while around me the winds are 150 mph. I can't let angry resentful people pull me in. It's unnatural to me and I don't understand it.
The good news is that you control your own actions and can reign in yourself. Think before acting. Hold your tongue before speaking. "Play it through", just like when tempted with a drink.