Preparing for the loss of a pet

I'm looking for the best book about preparing for the loss of a pet and/supporting one through a loss of a pet. There are a ton out there. I'd love for someone to point me in the right direction. Ideally, it's recommended.
My Golden and soul dog is getting up there in age and I know it's going to absolutely shatter me when she crosses the rainbow bridge. I want to prepare my heart as best as possible and give her the most loving care in her final years. Thanks in advance 🩷🐾