I assume you too have face this challenge to not to remember her or him after some fight but its seem impossible to do. As much we want to forget she/he keep coming in our imagination and we struggle with ourselves to not bring her/his face in memory.
So, I have a solution to this problem. Please note this is not for everyone and may not be applied in all situations. I used to follow this trick. Also this is not if you want to forget for ever but you may try it.
Here is the trick. Whenever you had fight then you show to her or him that you are angry and will not talk to her but not think same internally. Alwyas think that you still love her, you will never forget her and you will talk to her again after sometime. I mean never get yourself serious about breaking relationship for ever.
You will see the magic- how easy is it to live for few days without talking.
Let me know your experience on it.