Don't let innocent people take the brunt of your unfinished business... I learned too late.
When people disappoint each other, usually the reaction is the emotion of anger. And once we get past the anger, we usually replace it with fear of being disappointed or hurt in the same way again. These fears are the triggers for anger in our present life.
I am not a fan of giving in to triggers or using them as an excuse to "blow off steam" in the present. I do think they can provide useful indicators of the things that we need to work on. If we can confront the issue with the other person, confront it and put it to rest. If we can't confront it, we need to place boundaries for ourselves so we don't damage our present relationships.
Sometimes things are so painful and shameful to talk about that it precludes the sufferer from communicating their struggle with the triggers. For instance, I know someone who grew to hate cats because the person they lived with collected cats and wouldn't clean up after them. I could have an issue with that PERSON knowing that I personally adore cats. Or I could tenderly see that they could use support in this sensitive area and give them grace.
For me, I have a hard time sharing with others my sensitivity about money spent on me and my daughter. I started out poor, got poorer in the orphanage and then was whisked into a wealthy lifestyle. For some reason I triggered anger in my father about his provision that he used to accuse me of being ungrateful and undeserving. This birthed my own trigger of feeling like my worth was stolen from me.
Looking back, I think the core of my father issues were mainly unspoken and had roots in my father's past with his own father. It made me think that my father's issues with me weren't with me at all but his weird way of dealing with unfinished business with HIS father. And- my issues with my adoptive dad were colliding with his problems and also my biological father problems. It's as though we expected each other to solve problems that didn't even involve the other person. It was a complicated and doomed expectation that we had for each other.
Now that my father has passed away, I lament his pain. People in pain cause pain. I feel sorry that he never heard from me- "Hey Dad, I wish I could have understood you more so that I could have been closer to you." My guess is that his own father said those things to him and I just triggered that feeling of worthlessness in him unbeknownst to me at those ages.
At least for me- understanding changes everything; it doesn't EXCUSE, but it puts me on the express lane to giving others grace. I guess the uber level of grace giving would be to not require explanations for the dispense of grace. I still have many years to work up to that (God willing).