Has our 18 year old cat left home to die?

Question
   Even though I have been reading how some cats choose to leave home to die I am having trouble getting around the idea. Whiskers has been missing for over 24 hours now. He is without exception an indoor cat. Has never, ever been an outdoor admirer. We don't need to worry if the door is open or anything like that.
   I have felt very keenly this past week that things were taking a turn for the worse. He was more vocal, very restless for a couple days, unsettled in general.
  He has literally grown up with our children. It's very distressing. I believe he went out yesterday afternoon when I had the door open for five minutes for the dogs to go in and out. My fear is that I should have been more in tune somehow and allowed him to die peacefully with the vet. I feel as though I have let him down horribly when he has only been a joy to us.
   I would love some feedback and shared feelings.
  Thank you so much,
          Barbara

Answer
Hi Barbara.  Very sorry to hear this.  I fear you might be right.  In fact one of the most worrisome symptoms to me is when a cat who has always been indoors suddenly starts trying to dodge for the outside.  I've had this happen on more than one occasion.  And every time I've brought them to the vet, something has been seriously wrong (advanced cancer, kidney failure, liver failure, heart disease, and terminal viral illnesses).

Hopefully Whiskers has simply decided to explore.  But if not, you can't blame yourself, and he didn't blame you, either.  It's natural to look for someone to blame, and it's often ourselves.  The fact of the matter is, although you sensed something was wrong, there's no way you could've known it was this serious.  And I don't believe cats experience this same need to place blame.  I don't think he feels you let him down.  I think he simply accepted the circle of life.  His instincts led him to do what all animals MUST do.  All animals will die, and that's beyond our control.

The only way this can positively impact you is if you take the knowledge you gained from this experience and apply it to future experiences.  It took this same experience for me to realize that when a cat has a change in behavior, no matter how insignificant, a vet visit is in order.  And it also taught me that animals are unpredictable.  Those who were never interested in the outdoors may suddenly change their minds.

Take comfort in knowing you provided Whiskers with a wonderful, loving home.  And he exceeded his expected life span by several years.  He lived a charmed life compared to so many other cats.  And that's the part that matters most.  How he lived is more important than how he may have died.