Answer:
a part of life
The Buddha taught that suffering, which included unhappiness and dissatisfaction, is brought on by our desires and how we view events that occur.
When it comes to desire, The Buddha did not mean that we have to rid ourselves of all desire, just unhealthy ones or ones that do not bring us peace and tranquility. For example; lets say you really want a specific new car. So you work like a dog to get the money and then buy it. So, for a while you are happy. But then the newness wears off and now you want something else. So you work like a dog again to afford that. This goes on over and over again. Chasing things you think will make you happy.
As for events, there is an old Buddhist saying: "pain is inevitable, suffering is optional." What this means is that we should see things just the way they are and not attach to events our preconceived notions (judgements) about them. By adding onto events our conception of "how things should be" we turn events from just events to catastrophes and disasters. For example; There is an old Buddhist story that goes like this: A farmer finds a wild horse and brings it home. His neigbor says to him "Wow, that was a stroke of good fortune". The farmer (who is a Buddhist) says "maybe, maybe not". So the farmers son, while trying to break in the horse breaks his own leg. The neighbor says to the farmer "wow! that was bad for your son." The Farmer replies "maybe, maybe not". A few days later an army marches by and forces all the young men to join, but since the farmer's son has a broken leg, he can't go. The moral of the story is that things are as they are. Don't make them worse by adding your judgements to the events.