What Buddhism realizes is not the root of suffering, but the origin and liberation of all kinds of distress and confusion.
The eight great pains in life are not pains, but inevitable troubles.
Because it is not suffering, people's present life is more important than the past and the future, and the state of human existence is more important than death and eternal life.
Because only physical and mental distress, people's life will have all kinds of disappointments, will make us think.
Buddha never said that living is bitter.