Everyone reacts to anger differently. Some people see red and get violent, some people verbally abuse, and some bottle it up only to explode later on. We all have our own ways of dealing with frustration or anger. When someone gets on my bad side I retort with a couple of insults, and if they're really pushing it I plan gruesome deaths (a bit on the creepy side). No matter how you react it's important to draw a line. In the end, your going to have to deal with the guilt. The memory of each venomous word, and bruise you left is going to be embedded in your mind for life.
In the middle of a situation it is hard to stop and think about what you're doing but it can be done. When you feel the red edges creeping in and you know you're going to snap think about how much more you could teach them by walking away. You rely on the other person to hurt you in return so you can tell yourself they deserved it. If you never get your reply you are left with no choice but to own up to what you did and truly acknowledge that you were wrong.