Genesis 23:1-2, How Did Abraham's Wife Die?

Sarah lived to be a hundred and twenty-seven years old. She died at Kiriath Arba. 

//Do you picture Isaac as a young boy when Abraham took him up the mountain to sacrifice him? Most people do. But one wonders how he is able to carry the wood for the sacrifice on his back if he's a child.

Instead, according to both the Talmud and the Kabbalah, Isaac was a fully-grown man of 37 years old. Now, if we do the math, Isaac was born to Sarah when she was 90, and Sarah died when she was 127 years old, so that would make Isaac 37 years old. Thus Sarah died in the year God told Abraham to sacrifice Isaac, his son.

We can probably pin the time of her death down even further. After Abraham (and presumably Isaac) trudge back down the mountain after the aborted sacrifice, they head off to Beersheba. The very next thing we read is that Sarah died at Kiriath Arba (Hebron), and Abraham "went" to mourn for her. So Abraham never saw his wife again alive after he left to sacrifice Isaac. Batteries hadn’t been invented yet, so Abraham’s cell phone would have been no help. We are left with the assumption that Sarah died of heartache from Abraham travelling off to murder her only son.

So, God saves Abraham's son from sacrifice but the ordeal kills his wife?