No motivation

I'm a person who has no friends, No relationship. No matter how much I try, I end up being lonely, There was one person who was my world for last 10 years, but even suddenly she started avoiding me, post that I'm feeling Unmotivated and lacking the purpose to do anything, And having no friends in the place I work and locality is more frustrating. Is this the nature way of isolating a person. I'm feeling emptiness.