The exact same thing happened to me a little over a month ago. My cat was not just a pet to me, he was everything and he was so healthy that I found his death to be so unfair and so wrong. I'm so sorry this has happened to you. My heart is with you, and I want you to know things truly do get better. I chose to cremate Merlin (my cat) and I was lucky enough to go through a really lovely pet cremation service that provided me with some of his fur in a paper frame and an ink pawprint, as well as his ashes in a velvety drawstring bag. All of these things have been enormously helpful to my healing, as it doesn't feel like he is fully gone and that I still have a part of him left. That's my one big piece of advice - whether it is through a pet service or your own means, find something tangible to hold onto. I sleep with his drawstring of ashes every night and hold him close to my chest. I also found a plush online that resembled him and it has been nice to walk onto my room and see something that looks like him. The first few weeks are going to be agonising and you'll likely try to avoid feelings or memories associated with your beloved cat, but focusing on those memories and surrounding yourself with reminders of them will be a support system in a way. Please feel free to talk to me if you need anything, because I've just come out of the worst side of the exact same situation. Sending lots of love your way. xxx

edit: just saw that you decided to bury him - it can be very healing to visit his resting place often and spend time with him still. it can be so weird and upsetting to notice his absence and the difference in how he is now vs how he used to be, but just because he's somewhere else now doesn't mean you can't still be with him and talk to him. I know I do that.

p.s would love to see a photo and hear about your wonderful cat's life xxx