According to Elizabeth Kubler-Ross, when we are dying or have suffered a catastrophic loss, we all move through five distinct stages of grief. We go into denial, because the loss is so unthinkable, we can't imagine it's true. We become angry with everyone - angry with survivors, angry with ourselves. Then we bargain. We offer everything we have. We offer up our souls in exchange for just one more day. When the bargaining has failed and the anger is too hard to maintain, we fall into depression, despair, until finally we have to accept that we have done everything we can. We let go. We let go and move into acceptance. 
Grey's anatomy.