My cat's cause of death

On the day he died, my cat, Raymond, had fluid drawn from around his lungs to ease his breathing. It worked, but by later that afternoon his breathing problems were bad again and by evening the vet recommended euthanasia, saying that Raymond wouldn't have lasted long and only suffered.
It's common to second guess yourself after doing these things and I have. The fluid was sent out for testing and it turns out Raymond had a sarcoma cancer in his lymphocytes. I'm probably saying that wrong. The main
thing of interest, to me, is that sarcoma is the type of cancer that required amputation of my leg in February of 2018 and is likely to kill me in a couple of years despite that. It often affects the lungs and kills you that way. 
This makes Raymond a harbinger of sorts. 
Initially, I said to have him part of a mass cremation. Early the next day, I changed my mind opted instead to have him cremated solo and his ashes returned to me. Yeah, I know: Ten to one they just scoop out an approximate amount of ashes and say they're of your cat or dog. Nonetheless, I wanted to take him back to his home in some way. This kind of touchy-feely thing is not my way, though I'm polite enough not to judge others.
The pet crematorium put the ashes in a nice little box. It has brass fittings and a small padlock. Why a padlock? My guess is that it keeps kids in the house from opening the box to get a look at their late pet's ashes, an act that will lead to the usual bad things kids do. Spillage. 
My parent's ashes are in cardboard containers in a closet downstairs. My dead cat has it better than my dead parents. Perverse, no?

Cat away

    I had my cat, Raymond, put down at 8:45 this evening. After taking him home from his regular vet at 2:00, where I'd taken him because his breathing was bad, we hung out and napped together on the couch. I did, anyway. I woke up to find his breathing clearly distressed, worse than before. I took him to a vet ER at six o'clock. They did a work up and X-rays. The gist was that he would be dead in a few months at best and those months would be bad to start with and increasingly shitty with frequent trips to the vet and invasive procedures. 

    Advice to those faced with this dilemma: Think of the animal first, you second. Give the animal more weight.

    I held Raymond, kissed him, talked to him. A gentle death via a nice doctor who asked, when it was over, if she could hug me, to which I said yes, but please don't knock me over when you do, which is a concern of mine since having my leg amputated fourteen months ago.

    Now I have all the after things to do. Putting away his bowls, litter boxes (I had two), toys.

    Such misery. I don't plan on trying this again. I'll stick with the fish in my koi pond from here on out.

    Raymond and I had two months and eleven days together. There were enough good days for him (and me) that I'm glad I did it, I guess, but how is it that after such a short time my heart is breaking?