What Should Be Done?

Instead of forcing yourself to forget the past. Try to understand the nature of it. Try to realize the cause and the consequences of it. Thus the past which gave you tears will turn into a valley of blessings.

As an example...

You might turn back into your college life and sigh by remembering how you used to be happy with your friends. That past now give you a river of tears.

But do you remember how you felt when the semester exams were hitting you hard? "I'll be happy when I become independent and a star in my industry"

So, were you happy all the time back in college?