You have a very astute mom. What she says is true. Many terminally ill patients, especially children, will cling to life until they're given permission to leave. They linger painfully because of the pain the parents, family will feel with their passing.
I told my dad in his drug induced coma that we supported his decision I was the only one who said it to him. That it was okay, we loved him, he was a good dad, man and husband. When I said that we'd take care of Mom, I felt his energy shift, almost like he relaxed.
It's so hard to say goodbye. It's so hard to let go of love, yet such a gift to be there, to be the warm embrace, the loving cuddle, to be unconditional in your caring.
You gave your puppy a gift, a very painful one to your heart. And he was there for you in your darkest days, and shared the light of your life emerging.
I am so sorry for your loss, Rob, but so proud of what you gave. Are there pictures of him in the alternate universe?