Make sure you are not building up expectations for your next pet in losing the one you had. The way I read this I made me want to say that it sounds like your setting up expectations for your next pet to fill, and idk that’s not all bad, but if you aren’t mindful of it, these beliefs you hold and the space you hold for your lost dog might set you up for a disappointment in the first stages of your relationship with your next pet. Be careful grief hurts and might make you make impulsive choices out of lonelyness and desperation

I'm so sorry for your loss, I can't imagine how much that must hurt. I'm glad you were able to be with her in her last moments. I think getting a cat could be helpful, so long as you're allowing yourself to grieve your dog. Some breeds of cats are more likely to be friendlier and more sociable than others, so depending on your expectations for your cat in being emotionally supportive, I'd definitely do research. Pets like that are irreplaceable. I don't know what I'll do when my own cat passes. Sending support ❤️

You mention the self hatred emotions. I think I would encourage you to not judge yourself. It's easy to get caught up in romanticism for things being better in a general way. But I think it's more fair to offer yourself grace through your grieving. What are you hating yourself for, getting a new ESA?