If the problem can be solved why worry? If the problem cannot be solved worrying will do you no good.
ShantidevaThat which is seen and that which is touched are of a dream-like and illusion-like nature. Because feeling arises together with the mind, it is not [ultimately] perceived.
ShantidevaAll those who are unhappy in the world are so as a result of their desire for their own happiness. All those who are happy in the world are so as a result of their desire for the happiness of others.
ShantidevaWhatever happens, I will not let my cheerfulness be disturbed. Being unhappy won't get me anywhere and will dissipate all my goodness. Why be unhappy about something if you can change it? And if you can't, how will being unhappy help?
Shantideva