You will never understand everything.

That is the simple truth ! Try as hard as we can, we will never be able to grasp everything in this complex world. And that applies to everything in all areas of life. And the sooner we grasp this fact, we will sleep easier. There are many things around us that will remain slightly or otherwise out of our comprehension. People will behave oddly and we may never understand why. Things may go wrong - even right suddenly - and it won't make sense. Try working it out and you end up more confused. Sometimes, it is much better to accept the fact, that things have happened and we can't do anything about it and get on with our lives.