I had the same problem with my 15 year old dog
He would not eat and could not get up on his feet
Two days ago I had him put to sleep (killed)
I think I did the right thing because he was so lethargic
and not having any quality of life
I hated it and made an appointment to have him put to sleep
Thought It wasn't going to be so bad, but It really got to me emotionally
It's been 2 days now and I find so many things that I did for that dog
due to scheduling, I had to dig his grave site before he was dead, he was even watching me
was a very bad day for me . . .
I still want to feed him everyday