I was discussing this with a friend yesterday about why we think too much about past mistakes and why future makes us nervous and anxious. The conclusion of the discussion came as – We have to live in Present.
This is an excellent article on How to live in present which I will highly advice everyone to read. Here is the first paragraph
What does it mean to live fully in the present moment? It means that your awareness is completely centered on the here and now. You are not worrying about the future or thinking about the past. When you live in the present, you are living where life is happening. The past and future are illusions, they don’t exist. As the saying goes “tomorrow never comes”. Tomorrow is only a concept, tomorrow is always waiting to come around the corner, but around that corner are shadows, never to have light shed upon, because time is always now.