Tuck it Away or Say?

When you disagree with someones words or actions, is it better to say something or just let them be?

I've run into this and feel as if I need to say "Hey look what you're saying and how it is not making for a very pleasant moment." What is making you feel like you need to act or be this way? If and when I  do say something it is turned around to me... it's not what happened. I was right there, and I know how things occurred. (don't know for what reason, but...)

I guess I feel that situations somehow reflect onto me, even if it is the actions of others. I don't understand why certain moments have to be so uncomfortable. Yet, I know I need to let that person be who they are.