what is one example why human relationships are NOT important to Christopher McCandles?

Chris simply leaves every relationship that he has. His sister is a good example. She was probably the closest human being Chris had in his life. When Chris leaves, he barely communicates with her. He leaves no way for her to contact her. There are cryptic messages here and there but nothing to tell her anything specific. This causes great stress and sadness to not only his sister but his parents as well.