SEM8806 saidPresidents retain their titles of "President" for life.
Correct. Such titles, especially in the Federal system, are bestowed for life. Hence one is forever called President, Senator, Representative, Justice, Secretary, Ambassador, etc. Military titles of rank are also retained permanently upon retirement, though few of us use them in civilian life, unless we return to public prominence.
Technically I'm entitled to be addressed as Colonel, but I never point that out in social situations. An anecdote: a few years after I retired, my youngest son (then 6) asked me if I was once in the Army, since he seemed to remember me wearing camouflage.
"Yes," I answered, and thinking to impress him, I added that I had been a Colonel. But I got a blank look in return.
"Do you know what a Colonel is?" I prompted him.
"Someone who fries chicken?"
I laughed hysterically, and learned a needed lesson in humility. My entire 25-year career reduced to being a fast-food cook. Out of the mouths of babes...