Hello Porcu,
Everyone has anger. It can't disappear like that. To find out why and what cause the anger, you need to see what made you got angry with your boyfriend that you hit him. Relationship can be complicated and stressful sometimes but before you show your anger take a minute or two and start to think why are you angry with him.
I have a very similar experience too. I had a temper and horrible anger that one could not ever imagine and wonder. I then sat down reasoning to myself the cause of my anger. Is it me or the situation that I can't accept that I am getting angry with. It was both. I compromised and started to talk to myself first by expressing my anger to myself. I then started to see is it worthwhile being angry for it. What am I gaining from being angry? Satisfying my ego and myself. It is not worth. Or is there more then to be angry about.
If you get angry with your boyfriend just pause a minute or two and talk to him about the situation rationally and calm. Sit down express your feeling and concern. Express what you don't like. He may not understand or may avoid it but give you a change to control your feeling of anger. The result may not what we want. Nothing is what we want. But at least you can calm your anger yourself. Think about the good time you spend. Use the positive to overcome the negative. You can. Believe in your feeling. Control it.
