Love and Anger

Zach and I had an ugly fight late last night over something that I consider pretty serious. I was yelling and nearly hyperventilating. Luke was in bed and didn't witness any of it. I felt like I was pushed into a corner and could no longer be heard. I didn't have the words I needed. I am feeling hurt and dismayed by the anger that surged forth from both of us. I need to find better ways to communicate, and yet, at the same time, I wish Zach could find a way to just listen to my fears and not judge them.
Why do people who love each other sometimes hurt each other? I know I'm not alone in feeling hurt in a relationship. The question now is what to do with the pain.