Coming on late here.
My Mom and Dad are also in their 80's. My Mom will say things like "I can't help but worry" about any of us kids. I finally told her yes you CAN help worrying. Don't. You did your job, you raised us and we are living our lives. How we do that is our decision just like it was yours when you were our age.
Dolly is right.. it is like barking at a squirrel in a tree. My Mom will be the chief co dependent to my Dad until he dies.. and he will continue to be an angry miserable human being while enjoying getting her worked up if ANYTHING goes wrong for him, from losing his car keys to having to do something he doesn't want to do. My Mom will worry about us 3 kids until she dies.. and it isn't her job to worry over us. It is her job to enjoy her own life. "Father Knows Best..."
And this is in a family with no drug users or addicts.