Memory

When I walk out from the exams hall today,the first thing that comes into my minds is to call him and tell him how do I do in the exams.I remember I used to do that every time in the past.But,now,everything changes.While I was walking back alone,a tear drop down my face.I was just a person who lives in the past.The past has had such a great impact on me that I will have a mental break down whenever thinking about it.I can't run away from it since I can't change the fact that the past still belongs to me.In fact,it is part of me.I know I can't change the past but why it has to interfere with the present?I am torn between the past and the present.What should I do to walk out from the shadow of the past?