I like these quotes:

"Holding onto anger is like grasping a hot coal with the intent of throwing it at someone else; you are the one who gets burned"

"You will not be punished for your anger, you will be punished by your anger"

Try not to 'hate' yourself for getting this way - as mentally beating yourself up over this is only contributing to lowering your spirits and working against your ability to resolve the matter. Try to take a more objective and impartial position. You realize that your anger is not helping you and not contributing to your well-being - so you need to contemplate measures that you can take to improve the 'situation' and ultimately bring about a favorable resolution.