That was my first thought too. I retired about the same time the report says he retired and, if I had next to no life after that, even though I've never been a depressive person, I would have got really depressed. Even though I'm fighting cancer, I have a loving family and my Church ministry.
Maybe he ended it all at the place he last felt some sense of self worth. Unless he left a note, we'll probably never know. Thank you for your service, sir, and may you rest in peace.
Unfortunately, that is the pattern. Return to the familiar for a final moment of comfort.