It's possible. The thing with a trigger for me is it usually effects me for a while after. Like you said, once the person does that then everything about them starts to irritate you.

Like for example, when I get left out of something on purpose, it will send me into panic. I start trying to figure out why I got left out. I start to feel like I'm a horrible person and no one loves me. I start going into major cycles of negative self-talk. This sets up a pattern of obsessive thoughts trying to figure out how else the person/people might also have been "against me" or trying to hurt me. And if I do not take steps to try to stop it, these process can go for not just hours, but days, sometimes weeks... sometimes longer... and this will be like a pin in my side, stuck there, and I can't seem to escape it.

This particular trigger is one I have to work on with myself. Of course I can't be included in all things I want to be included in, and of course being left out doesn't mean it was "on purpose," or even if it was, not meant in offence. It's very difficult for me, and I am still working on coping with this particular trigger. The closer I am to someone, the worse I react when it happens.