Anger is often generated by disappointment because of the gap between what we expect and what we get in relationships, in life, or on our jobs. Some research shows that the problem is not so much the “reality” of the situation, as your expectation of it.
In martial research, for instance, a consistent finding is that there is a large percentage of issues in any relationship that will always be there – as long as you are in that relationship. Go to another relationship and there will be another set of “perpetual” issues that will arise and potentially cause conflict. Research more specifically shows that 69% of the time couples fight over unsolvable issues.
Learning to adjust expectations and accepting things as they are (and then compromising or restructuring the relationship) can go a long way toward resolving anger and leading a happier life.