Monday's Riddle! Two Sides to the Story...

Hello Riddlers! Here we are again on this lovely Monday. Lizzy may see it differently ; ) Can you guess the theme this week?

Words twist and turn, there's tit for tat- she saw what I saw, I can tell you that. But he didn't listen, and went on his own way- though, that's surly not what he would tell you today. 

It's all in a notion, at the scene of the crime. What could have happened? Who broke the line? One will hear this, one will say that- who really knows where it's all at? 

There's two sides to each story, so they say- I am the thoughts that like to see it your way. 

What am I?

I gave you a clue!