Saying goodbye to your best friend

The Vet say that it's getting close to the time for me to say goodbye to my best friend, but I don't know how to do that, and it's nothing I've ever had to do before. I'm gonna make sure it's done at my mom's house of course, where she is the most comfortable and happy. She can no longer make it to her bedroom, so she sleeps on a big dog bed, but she can no longer roll around in it due to her leg being in pain. The vet put her on a new medication but I'm not sure what difference it will make. I spend a lot of of my daytime sitting next to her and letting her have bites of whatever I make to eat and spoiling her and trying to take her places but she still ends up sleeping most of her days away. I know I'm not ready, but it's coming for me anyways. I love you Leila. You've been here for me more than anyone.

This is for everyone going through this or who's in the process of it. It's impossible to accept. I hope you all stay strong.