I felt bad knowing Jake's fate. I felt worse (for you and me) when I read you had to put him down so suddenly.
But then I saw the pics.
I believe animals know when they're loved, and that Jake appreciated everything you did for him.
Several years ago my 17 year old cat suddenly couldn't move his rear legs. The next night when I got home from work I took him to the vet, and that was the end. He had numerous ailments, that along with his age made for little chance of a decent life going forward. Standing there holding his paws while he passed I thought of so many things we'd been through, and I realized how big a part he'd played in my life. If there is an afterlife, he deserves the best, and I hope he knows what he meant to me.
I feel your pain. Consider yourself guy-hugged.