To prevent disappointment, expect nothing from anyone.

The 2 beautiful quotes that come to my mind when I hear this are :

1. "The most amazing things that can happen to anyone can happen to you if you lower your expectations" - Phil Dunphy from Modern family

2. "Keep your expectations on goals , not people. People will always disappoint you. Goals will never. " - Dr. APJ Abdul Kalam

If u understand this then you won the life!