People are doing what is right in their own sight. If a shirt's got a light tear, throw it away. If you don't have the money right now, put it on credit and pay it off later. If you've put too much on said credit, and some little unforseen event occurs, then take bankrupcy and you can get more credit right afterwards. Take medicines, surgeries, cosmetic procedures, and quick-fix diets to patch up what ails you or what is inconvenient. Marriages are as disposable as the $5 dollar cameras we can now buy.
It's the ultimate expression of the hippie concept of "what feels right is right". It was possible for the "peace and love" anti-materialistic children of the 60s to turn into yuppies because it feels really good to make some (or even a lot) of money. A second income in a fulfilling job is good to keep even when it ends up costing more to go to work than to stay home.
The ultimate expression of this has been a quote I've heard often during the Terri Schiavo case: "I wouldn't want to live that way". Of course you wouldn't. I don't want to be brain-damaged either. Number 1 son didn't want to lose half a lung to pneumonia. My mother-in-law didn't want to die from ovarian cancer. TheAnchoress' brother-in-law S didn't want to die a lingering death. John Paul has no desire to slowly deteriorate from Parkinsons.
Job didn't want to be tested by Satan either, but when God answers Job, God doesn't justify Himself. He doesn't justify Himself to us either. Instead, there are times in our lives when we will have to do things, be places, or even give up things we hold dear (even our health) because of God's plan for us.
By interfering in God's plan by unnaturally ending a life (and y es, withholding food is ending a life) is the ultimate rejection of God's will. I don't know why Terri Schiavo is in the condition she's in. She may be there from abuse, or a potassium imbalance. She may be PVS, or "simply" severly brain-damaged. It might be that Terri will never return to even a resemblance of her former life. Nonetheless, what does it say about us when we are willing to throw her life away because she is no longer convenient to her husband or society.