When we overthink, so many thoughts are generated. The thoughts act like bricks to form complex buildings. We fill the gaps to make connections. The buildings that are formed appear beautiful. Complexes made of thoughts include theories, fantasies and stories.
Problem is, when we fill gaps by making wrong connections, reality that has to occupy the gap will find no place for itself. So whole building of thoughts collapses, when we encounter the reality.
This process of making buildings of thoughts and breaking can not only drain the energy, but also can make us live in virtual world.
It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. – Sherlock Holmes