LOL A little bit of expert googling and found it. However, I do not know who wrote it and who does it on the folk scene.

I Can't Remember!

Just a line to say I'm living,
that I'm not among the dead,
though I'm getting more forgetful
and mixed up in the head.

I got used to my arthritis,
to my dentures I'm resigned,
I can manage my bifocals
but God I miss my mind,

For sometimes I can't remember,
when I stand at the foot of the stairs,
if I must go up for something,
or have just come down from there.

And before the fridge so often,
my poor mind is filled with doubt,
have I just put food away,
or have I come to take some out?

And there's the time when it is dark
with my nightcap on my head,
I don't know if I'm retiring,
or just getting out of bed.

So if it's my turn to write to you,
there's no need for getting sore,
I may think that I have written
and don't want to be a bore.

So, remember that I love you
and wish that you were near
but now it's nearly mail time
so I must say good-bye dear,

There I stand beside the mailbox
with a face so very red,
instead of mailing you my letter,
I opened it instead!