Anger, one of the most powerful emotion. Why we are angry? Cause we are Humans. We have emotions, our whole life is surrounded by those. Angry at girlfriend cause she is not giving enough time, angry at boyfriend cause he is so careless sometimes, angry at boss cause he/she is pushing too much, angry at neighbors cause they are such a pain and husband-wife thing is everywhere as you can see. Pretty much you're angry at everyone. Reasons, simple one...you're expecting too much from them. You're getting your hopes high without evaluating things but that is Human nature to expect. If you say you don't expect anything you are simply lying to yourself. Expectations will always be there quantity may be less or more but it will always be there. There is not a single soul on Earth that doesn't expect anything. So when you don't get what you expect you either become depressed or it manifests into Anger. There is only one case when there will be no expectations, when you are not close with anyone in simple words No bonding with anyone which is almost impossible, everyone is bonded one way or another that is human nature to be bonded with others.
Channeling anger in positive way is very hard thing to do. I have tested it myself. At one time it sounded almost impossible but of course nothing is impossible in this world expect one thing. Suppressing the anger is not a good idea it may sound good on short term but on long term it will be more destructive, much harder to manage, the best thing to do is let it out little by little. Without hurting anyone specially not your ownself. Cause history is filled with examples what happens when you suppress the anger for too long and it manifests into something else.