But what you need to realize is that "you are not upset for the reason you think."
You think you're upset because of what a person did, or didn't do, or what happened, or what you saw. You think something other than yourself caused it, or that something's happening beyond your control. But this isn't really why you are upset.
You're having an experience right now of upset and fear and guilt and anger and shame, and that is inside of you. Its yours. But the main problem is you've placed the cause of this experience into something separate from you. You think it's that person who put these feelings there. You think it was that thing happening that caused this upset. And you see yourself as having been unfairly victimized by them. And now you're suffering and you can't get out of it.
Well all of this experiencing is inside you because it's yours, and it was already inside you BEFORE this person or event came along. You had it stored away in the back of your mind, unhealed. You are already full of all the upset and fear that you could possibly need to account for all of your upsetting experiences in every lifetime. You don't even need to find extra causes for adding "new stuff".
This upset that's in you wasn't put there by anyone else. It wasn't just created in you by some event that just happened. Nobody made you feel this way. Nobody is doing anything to you.
This is old stuff. It's always old stuff. Its the sense of sin and guilt from separating from God that you buried in your mind long ago, coming up inside of you to remind you of how you feel. And yes, it was maybe "triggered by" someone or something happening, or what they did, and because it was triggered by them you mistook this to mean it was caused by them. But all they did was mirror to you how you already felt, deep down, and so it popped into your awareness. And you asked them to do this for you.
Its not their fault.
This is about you. Its your stuff. Your feelings. Your experience. Your attitude. Your beliefs. Your way of looking at yourself. This is about your sense of separation from yourself and God and how you haven't forgiven yourself for what you think you did. That's what needs to be forgiven. You CAN'T forgive anyone else because nobody else is capable of doing anything to you!
You need self forgiveness. And that entails admitting that all of this stuff is self-inflicted and self-chosen and it's all your own stuff. It's not anyone else's fault. Nobody has made you feel this way. You agree that you should feel this way.
And so then, why do you feel this way? What is it you believe about yourself, in relationship to God, that has brought about this nightmarish experience? This fear, and guilt, and sin? Is it really true of you? Is God really against you or upset with you? Is he really abandoning you? Do you really need to be afraid of his revenge? Are you really a sinner?
Will you forgive yourself and recognize that you have NOT done what you thought you did, that it has had no effect on God whatsoever, that you are still innocent and loved? How about some relief, in knowing that nothing's gone wrong and you're still worthwhile? Or that God still unconditionally loves you right now and always will? That you haven't made Him go away and He isn't bearing any grudge or anger toward you? All you really want is to love and go Home.