I often hear people say "...It pisses me off...." when referring to something that's bothering them. The way I see it, it's not the object or stimulus that's *causing* the upset, it's the person's *reaction* to the stimulus. I know I have the choice to let something (or someone) bother me, or to not let that something (or someone) bother me. Even it's a split-second kneejerk reaction, it's still a choice.