It has occured to me that working with lawyers has taught me to be fluent in a language I didn't know existed. Yes, I can now speak fluent Asshole, often without realizing it.
Buying breakfast the other morning, this guy cut in line right in front of me, and I let loose on him. The entire time he was checking out (instead of me). It wasn't until an hour or so later that I realized I had lapsed into Asshole without knowing it. Why did I need go Asshole over losing 15 seconds? It's not worth the stress. Besides which I was running early.
Admitting you have a problem is the first step. "Hi, I'm Grumpy, and I am an Asshole..."