From now on everything has a different meaning. A simple thought can transform us and make us reflect upon existence. Someone said that our thoughts are the shadows of our feelings. Evil thoughts or pure thoughts. It depends of their nature, that is what actually makes the difference. Our thoughts can somehow change our world. Friedich Nietzsche said,
"I'm not upset that you lied to me, I'm upset that from now on I can't believe you."
It is that kind of thought that hurts. Indeed, it causes emotional pain.
Even if I don't like the idea, I must recognise that everything depends on the way we see things and the importance we attach to them.
"That which does not kill us makes us stronger."
In fact, we are attacked by ideas and thoughts that build up our personal world. It is within the natural condition of life. There is always a thought that leads to reflection.