Can Fear and Cynicism Actually Cause Pain?

I learned that one reason for end of life pain is holding on desperately to life out of the fear of dying. Other terminal people suffer at the end of life because they have become cynical about life itself, having found no deeper meaning in their own. All the things people learn to do to numb themselves and distract themselves from a lack of meaning in their lives stop working at the end and the collective pain is suddenly and overwhelmingly expressed.