Why is Buddhism so negative and pessimistic?
Buddhism talks a lot about suffering and impermanence because living beings are very strongly attached to life and to the enjoyment of sensual pleasures. It is this attachment and enjoyment that is the cause of suffering. If one follows the Buddhist path, attachment is gradually reduced and finally eradicated altogether. The complete absence of attachment is the highst possible bliss. Even a little less attachment means less suffering, so Buddhism is a path of joy and liberation from pain, dissapointment, grief and despair. It is not pessimistic at all.