Often when we lash out at our mate it is usually because we have been triggered by something they have said or done. This is common because most people hold on to our difficult feelings and they reside somewhere in the body.
Someone we love says something to us and we explode. This is common too. If you are in a relationship and your loved one just reacts when you say something, it’s probably because you touched something that resides in his or her body and this feeling has been out of reach until you triggered it.
That’s why psychologists call these out of the blue reactions triggers. They probably make sense to the person who is reacting if they have spent time wondering why they act the way they do.