I am so sorry to hear that Mimi is declining. I worry about this with my Tabitha, who recently turned 18. I would agree that your heart has to guide you. Tabitha has mostly good days, but sometimes I can tell she is slowing down, especially in the winter and colder days, and on humid days.

Love Mimi all that you can... and let her do what makes her the happiest.

That is the best advice that I can give you.