I can only imagine to what extent anger can lead a person. The worst thing is that some don't even know why they are angry. Really, is it because you do not agree with what the person has done? Is it right to judge a person as you base it on your own standard? If so then I dare say that you have condemned the person and have not given him the chance to be sorry for what he has done and have refused him of his right to walk in better judgement moving forward.
As I see now how a simple disagreement can lead a blinded heart to anger and how anger can be fully capitalized to become bitter. No explanation will be worth it. A person who has been wrapped up in his been wrapped up in his "own disappointments" will never open up himself to any idea except that which agrees with his. Yes, it is his disappointments that makes him angry. It is now about the object of his anger. The only reason for anger to become full blown is when you try to reconcile other person's wrong doings with what you want. Much to an angry person's dismay, other people's faults will never be reconciled to how you run your life. His faults are not yours so much so that your faults are not his. You are the one responsible for your action as other people are responsible for theirs.
Will there be a solution? Of course. Forgiveness. It is the only thing bigger than our emotions to actually learn to see beyond what has happened. Your forgiveness is not synonymous to your belief. Surprisingly, one can actually forgive and forget without meaning to compromise what he stands for. How can this happen? Simple. You are not judge people. If we remember that, we would know the secret to having a peaceful life.
I'll say it again, in such instances, wisdom is the only thing we will ever need.