Borrowing trouble is not normal

Remember that Rashi -- the one in which he refers to the rabbi who answered the question, why did Hashem go ahead with his creation if he knew that he would be disappointed in man? I looked it up. The Rashi is on Bereishis 6: 6 on the words, vayitatzev el libo, meaning that Hashem, so to speak had sadness of heart because of the wickedness of (hu)man(ity). Rashi says, "and this is what I wrote as the answer to a heretic who asked Rabbi Yohoshua ben Karcha: 'You concede that the Holy One Blessed Be He sees what will happen?' He answered, 'Yes.' He [the heretic]proceeded to say, 'Doesn't it say that He had sadness of heart?'[Why should he experience sadness if he knew what would happen?] The rabbi then asked if the heretic ever had a son born to him. He answered "yes." The rabbi asked 'And what did you do? [when the baby was born]' He answered, 'I was happy and celebrated with others.' the rabbi said, "And did you not know that he is doomed to ultimately die?' The heretic responded 'At the time of joy, we are joyous, and at the time of mourning, we mourn.' The rabbi explained 'such are the ways of the Holy One Blessed Be He; even though it is revealed to him that humanity is set to sin and to be annihilated, he proceeded to create people for the sake of the righteous that are destined to come of them.'

What brought this up? Someone told my daughter that she cried for hours when thinking about the fact that her old dog will soon die. Such a maudlin view is the very antithesis of the Rashi above. You see, the Torah assumes that people do not dwell on the fact that, yes, all mortal beings will die at some point but live in the present and celebrate the joy each moment brings even when they know that life is transient.