There is really no point in being upset about the inevitable.
If you cannot change what is happening, getting angry, frustrated, or worked up over the situation will not improve it.
Likewise, if you do have the power to change your circumstances, being upset will not make doing so any easier and choosing not to change things is no excuse for self pity or resentment.
Mind you, there is a time and a place to be upset.
We are not meant to be emotionless creatures who accept every happening in our lives as fate.
Some experiences are truly upsetting, painful, or even intolerable.
The point is that being upset about what you cannot change, or even what you can, will not make your life or your circumstances better.