Please bear with me, I will contemplate the whole forest and zoom in on the tree that is your Jeremiah.
It is shocking how humans can lose all rationality and become sub-human (for to say they become animals insults the animals), inflicting pain and suffering with no purpose in mind (as if pain and suffering could have a purpose).
There is an abstract yet important thing to keep in consideration. In your country, there are LAWS that PROTECT your beloved cats. Any person that causes harm to them is BREAKING THE LAW. Such laws do not exist in most countries. I am mightily impressed at how in the United States, during an evacuation due to natural disaster, there is a concerted effort to help animals in peril. A wise man said that a Civilization is measured by how it treats its' animals.
And yet, one look inside a slaughterhouse speaks volumes about our smug ignorance and self-delusion. In essence, we are still little more than ancients with a bit of industry.
But then, look at cats, and you can see that they do the same as we do. Conversely, we do the same as they.
I rescue as many mice as I can from the clutches of my cats and feel terrible every time I am unable to save them. I go absolutely livid whenever they catch a bird. Cats are hunters, they are killers. Sometimes, they hunt and kill for target practice, and leave the mouse lying on the ground. And yes, they are sometimes hunted, be it by dogs, by people or by OTHER CATS.
In the large picture, one in which we humans, like cats, are both hunter and hunted, your Jeremiah was a robust spirit, for he lived a life surrounded by love, and this should make you feel happy and proud, even as you are in pain. While Jeremiah lived, he was never alone and surrounded by indifference.
This perspective, our place in this grand cycle that I do not like yet is beyond my control, helped me when I lost Movi at the hands of a savage I tragically trusted.
May all your cats be safe, from now onward.