I read most of this thread and I am so, so sorry to read this terrible news.
Know in your heart that you did everything possible that anyone could have to help your precious Anika. My heart goes out to you.

We will all be there with you and Anika during this painful time.

Go peacefully dear Anika and let your meowmie know that despite everything that she has done for you, that you just could not fight anymore. You are ready to go on to the RB, where you will wait for her, one fine day.