Let Go.

Our own attachment to things is our greatest downfall. Obsessive thoughts about certain 'its' can only pass if we acknowledge them as only thoughts. We can learn to appreciate things as they happen and as they pass, let them. We can avoid disappointment by avoiding expectations and promises, expecting the worst can lead us to appreciating more! By letting go we liberate space in our mind. I like this story because it reflects the concept:

A great Buddhist teacher has a beautiful vase in his room. Everyone who visited him admired this exquisite vase. One day a student came to visit and opend the door clumsily. The vase fell to the floor and smashed to pieces. the horrified student started to apologize, but noticed that her teacher was smiling and didn't seem upset that his beautiful vase was broken. the student asked her teacher why he didn't mind losing his precious vase. The teacher replied: "I always told myself the vase was already broken, so when one day it did evitably break I would not feel its loss. you too can learn to let go of your precious possessions in this way."