Your Mindset comes from a combination of your life experiences and the decisions you have made.
Combined, those choices become the bases for future choices. The entirety of your life creates a map that you refer to in future decisions.
Each of these decisions sets up a pattern of vibrations that is unique to you. In Quantum Physics, we know that the universe is made up of vibrating quarks. We also know that these quarks are synchronized instantaneously without respect for the limitations of the speed of light.
Our human nature is similar. When you meet people who are vibrating in a similar fashion, you feel instantly connected to them. People who vibrate differently tend to feel wrong.