Teach me your way, O LORD, and I will walk in your truth; give me an undivided heart
You have no control over a primary emotion, developed in the past, when it is triggered. It doesn't do any good to feel guilty about something over which you have no control. But you can seek to resolve the past conflict and you can immediately evaluate the present circumstance to bring it into perspective. For example, suppose you meet a man named Bill. He looks like the Bill who used to beat you up as a child. Even though he's not the same person, your primary emotion initially jumps to a 3 on a scale of 10. But you mentally tell yourself that this is not the same Bill, and you think yourself down to a 2.
You have not only used this process yourself thousands of times, but you have also helped others do it. Someone flies off the handle, so you grab him and tell him to get hold of himself. You are helping that person gain control of himself by making him think. Notice how this works the next time you're watching a football game and tempers explode on the field. One player grabs an enraged teammate and says, "Listen, Meathead, you're going to cost us a 15-yard penalty and perhaps the game if you don't simmer down." The player will see the conflict in perspective and will get himself under control by thinking clearly.
Some Christians assert that the past isn't important. If you're talking about truth, then I would agree. The truth is truth--past, present and future. But if you are talking about what people are actually experiencing, I would have to disagree. Most of the people who argue that the past isn't important have major unresolved conflicts from the past which they are not allowing to surface. They are attempting to handle themselves by living in denial. Either that or they are extremely fortunate to have a conflict-free past. Those who have had major traumas and have learned to resolve them in Christ know how devastating the past can be to present reality.
Prayer: Lord, I choose not to live in denial. Give me the grace to look at my past and the courage to face the truth.