so sorry to hear of your dilemma, I know exactly how you are feeling and the questions that you ask and ask again, I was in a similar position with my special girl Bracken a few years ago,
just go with your heart and I am sure you will do the right thing for your special Jazz, make the most of each day, and what ever decisions you make you know in your heart it is the right one made with love.
it broke my heart when I lost Bracken, and I cried a river of tears, but two years down the line, and with a clearer head, I know it was the right thing to do when I did make that decision
take care of yourself and give a hug to Jazz
love Maria