"And Abraham said to his servant of the household. I bind you by an oath that you will not take a wife for my son from the daughters of the Canaanites" (24:2). 
 
Though Yitzchak was approaching forty he had made no apparent effort to find a wife. Left to his own devices he might never have married. It was only due to the initiative of his father and the diligence of Abraham's servant that Yitzchak did actually marry. 

While we often talk of the special bond between Avraham and Yitzchak forged for eternity in their march to the Akeidah - it seems that Yitzchak was actually much closer to his mother. While it was Abraham who took Yitzchak to be sacrificed, if not for Sarah who knows what may have become of Yitzchak. "Drive away the slave together with her son" (21:10). It was Sarah who, against the protestations of Abraham, insisted that Yishmael be evicted, thus removing a potentially harmful influence upon Yitzchak. Undoubtedly the experience of having nearly been slaughtered by his father left its emotional scars. How could it be otherwise? 

Pointedly while the Torah twice tells us that on the way to the akeida that father and son walked together after the traumatic events of the akeidah there is no record of any discussion between Abraham and Isaac. This despite the fact that Abraham lived for at least another 38 years after the akeidah. The only time they appear together again is at Abraham's funeral. Ironically while the walk to the akeidah was father and son alone - "Abraham said to his young men stay here with the donkey; the boy and I will go to that place alone"(22:5) it is Yitzchak and Yishmael who bury their father. It is as if the special bond between father and son is no longer unique to Yitzchak, "I will also make the maidservants son into a nation for he is your seed" (21:13).
  
If we are too assume, as some traditions do, that Sarah died of an apparent heart attack upon hearing of the near death experience of her son the tragedy of the loss becomes magnified. As Yitzchak is being transformed into a 'pure offering' it is his mother who is the ultimate sacrifice of the akeidah. The akediah thus becomes for Yitzchak a painful reminder of the loss of his mother.
  
Furthermore it appears that Yitzchak did not have an opportunity to mourn for the loss of his mother. From reading the Biblical text it would appear that Yitzchak was not even at the funeral. It is Abraham and only Abraham who negotiates the purchase of a burial plot for his wife. "Abraham then buried his wife Sarah in the Machepelah field" (23:19). Where was Yitzchak?
  
While the Torah records the eulogizing and weeping of Abraham we are left to speculate as to the reaction of Yitzchak. Perhaps Yitzchak was too traumatized by the experience to mourn properly; after his experience he was in a state of emotional turmoil. It is noteworthy that Jewish law states that one should not be informed of the death of a relative if such news would be too traumatic and likely to be psychologically or physically devastating. Perhaps Yitzchak "blamed" himself or his father for her death and was too distraught to even attend the funeral, or perhaps he didn't even know his mother had died until much later.
  
By never properly mourning, Yitzchak was unable to gain comfort. He was deeply depressed over the death of his mother and could not believe that he could find love and comfort with another woman. It was only upon his marriage to Rivka that he could begin the healing process. "He took Rebecca and she became his wife and he loved her. Isaac was then consoled for the loss of his mother" (24:67).
  
Chayei Sarah deals with the cycle of life, the tragedy of death and the joy of continuity through marriage. Our 4,000 year link to our tradition is the greatest comfort we have as we face the challenges of a very dangerous world. Shabbat Shalom!