Oh Greet, you have touched on something I've given thought to lately as well. I'm dealing with a similar work situation and finding myself annoyed more than normal.
I'm guilty too, but what is funny is that I am guiltiest when someone triggers huge resentments in me...and therefore I really need to do my own inventory to deal with those resentments.
I find it hard to express my own thoughts or opinions at work when someone is waiting to find any fault they can or just throw in negative remarks that have no substance.
My thoughts are that I wouldn't let anyone get away with this in my "out of work" life, so I should be able to express my feelings appropriately at work too, perhaps by taking the person aside and just telling them how I feel.
Also. take a look around next time and I'll bet others are walking on eggshells too rather than confront or deal with this person who annoys you. Sometimes just calling the annoyer on their behaviour is enough, sometime just remembering that anyone that unpleasant may have something bothering them and that they are sick people who could use our prayers.
We don't have to allow negative people to infiltrate our positive energy. That's something I will make a point of remembering today.
Hugs