Depending on your life experience, at some point, you need to start hiding certain stuff like emotions, events, bad memory. For me it's emotions.

I have probably experienced enough emotion to fit a persons life time. I've seen death, I've felt and still feel love, I feel anger and I feel confusion. Unfortunately, there are always people in your life that you can't shut out as much as you want to and at some point you start hiding things. 

What for? To save yourself and to save your beloved pain and sadness.