Your post resonated with me this morning.I was so sad for you.Its the utter disbelief and shock of being smacked with a diagnosis that is set in stone.
I had the same a month ago with my 6 yr old schnauzer..bladder and colon tumors ….prognosis 2 to 4 months.
At least I’ve had time to digest this,but it’s still a bitter pill.
I absolutely think you’ve done the right thing by your dog and he’s pain free.You will carry this with you,but keep thinking he’s now pain free,you did things right by him.
Im sorry for your loss.He looked a magnificent boy.