Personal Confession ~ To know or not to know

Lately I have been pondering to myself about life and how things as you grow and develop start to either make sense or get more complicated. I have been questioning whether it is better to know something is wrong or not.

……..Let me give you an example……

Is it better to know you have a disease that will eventually kill you or is it better not to know so you can go on and enjoy your life? Because I am one of those people who once I know it brings me down a 100 fold and getting back to my joyous self becomes tough and tortuous.

  I have always said that for me ignorance is bliss but lately I have found myself questioning if that is still true. One might argue that once you know then you can do something about it, take precaution or start treatment but there is another side to knowing it depresses people and for most the depression is stronger than the need to take precautions or start treatment.
One might say it is best not to know as not to tip the equilibrium and continue on living as if you will live forever. Though one might think this is ill advised sometimes I feel like this is an approach I want to undertake for my sanity’s sake. 

A couple days ago I stumbled across something I am wishing I didn’t know and would give my right arm to forget but that won’t be happening I know it already and now I am wondering if I should get involved or stay out of it and pretend I know nothing. The internal conflict is so strong that I have resorted to documenting it here as most times when I share things on here I get clarity that I don’t usually see when alone in my thoughts. 
What would be your approach, to ignore or to disturb?