Hi Changhi. You posted this question awhile ago, I hope you're feeling better.
What I too can share with you is from a Spiritual stand point. I can completely relate to your feelings! It is so easy to hold onto anger and resentment isn't it? And I found out why!!!! It's not you, it's a demonic spirit in your life that is really hard to get rid of!!!! It's an ugly one we never want to claim.. named IDOLITRY! Let me just say this before I go on.. Knowing God is very humbling.
Many times in my life I was so mad about the way I was treated, I had so much resentment and anger, unforgiveness because of things that had happened to me! It just wasn't fair! Then one day God revealed something to me.. there are 2 types of anger, one infact is a healthy righteous anger that is fine to have for a short while. We should be angry about injustus, even God and Jesus got very angry, and I'm sure still do! But then there is this other kind of anger that once it gets it's claws in, turns on us.. and is strait from the pits of Hell!
Satan, and his demon hosts are here to do nothing but kill, steal and destroy.. John 10:10. And wouldn't you agree.. are really good at it! Satan's main purpose is to steal your life away however possible. Anger, hatred and resentment are his favorite tools to use against God's people. Think about all the people who are rude to one another, who stir up anomosity and rage, some go their whole life pissed off and offended because of what has been done to them. Satan loves this, and is always right there to fan the flames.. he wants each and every one of us Angry and hurt, his ultimately goal is for us to kill eachother and kill ourselves!.. to completely destroy God's precious gift to us, (Life, Love, Peace and Eternal Salvation).. things he will never again have. In the Bible it says that our war is not against people, but against Rulers and Spirits in high places.
We have to fight against these attacks on our minds every day, until we finally gain authority, where the devil has no more power in our lives! Here is a scripture I want to share with you; Romans 8:14 For all who are lead by the Spirit of God are Sons of God. Matthew 12:9 makers and maintainers of peace, for they shall be called the Sons of God. John 16:33 Jesus said; "I have told you these things, so that in me you may have peace and confidence. In the world you will have tribulation and trials and distress and frustration; but be of good cheer (take courage; be confident, certain, undaunted)! For I have overcome the world. (I have deprived it of power to harm you and have conquered it for you.) Jesus also said; "Peace I leave with you; My own peace I now give and bequeath to you. Not as the world gives do I give to you. Do not let your hearts be troubled, neither let them be afraid. (Stop allowing yourselves to be agitated and disturbed; and do not permit yourselves to be fearful and intimidated and cowardly and unsettled). You heard Me tell you, I am going away and I am coming back to you".
There are also so many great scriptures on Forgiveness. God is so wonderful and smart, He is all powerful. You never walk alone in your struggles here on earth when you have a personal relationship with our Heavenly Father. Believe me! He loves you so much, and He knows everything you have been through and how you feel about it. I was going down the tubes, filled with so much anger and resentment.. even now, sometimes that demon will try to rear it's ugly head again, and I cut it off at the knees! Sometimes I have to yell out.. GET THEE BEHIND ME SATAN.. YOU ARE NOT WELCOME HERE ANYMORE! GOD LOVES ME! I AM A FORGIVER! I HAVE PEACE THROUGH JESUS CHRIST! AND I WILL NOT ALLOW YOU TO STEAL MY SALVATION!!! Sometimes I get so mad at the little thoughts he tries to dump in my head! Things that happend years ago! Who cares! It's over!
It's gotten to the point in my life that I am fed up with the devil messing with me. He is worse than what he had any person do to me! One day God's people will be able to look at this little thing that tormented us all of our lives and be able to crush him under our foot! I say let's start now! Don't let Satan control your life or your thoughts anymore! Find that place of peace and forgiveness. Put on the full Armor of God! (Ephesians chapter 6)!
Take care of yourself brother, or Sister. See ya on yedda!