I read some books about verbal abuse that helped me understand anger/people who are controlling. They were by Patricia Evans. She's a therapist and really understands the dynamics at play.
I also found the books by Carl Alasko, PhD, to be helpful. They're about toxic emotions and are insightful in terms of understanding what causes toxic emotions, how they flourish, and how to stop them. The author is a therapist and had a great system for a couple to talk through issues without blame, and thus without needing to "manage" anger, because they could resolve their problems without bringing blame into it. (He has a whole book about blame, because it is so toxic, insidious, subtle, and harmful to relationships. He also shows how so often blame and anger are tied together/build upon one another.)
Patricia Evans and Carl Alasko -- their books are some of the most enlightening books I've ever read because they talk about the dynamics of verbal abuse and toxic talk and you can see it yourself so easily once it's pointed out to you, in so many situations, whether on a large scale or in your personal life.
I learned somewhere in these books that anger is often a lashing out that happens after someone has been hurt, or feels something is unjust. Anger is a feeling ultimately that helps us know when things are unfair or wrong, a tool for understanding life, but it can so often be destructive and escalate to violence, especially when its basis is not in reality (irrational anger).