I'm not a regular anymore. I had been caregiver to my MIL for 18 months, up until February 9th when she passed away. I've been checking in now and then and came across your post. You have presented a challenging question. I don't think even the best theologians could answer this because these are the feelings in your tender, hurting heart.
Like Mimi, I too wish the answer could be put in words for you to read and feel a resolution. But that will never be. We live in a world with forces of sickness, destruction and hatred pulling from every direction. If it weren't for all the goodness, love, support and forgiveness we receive from all those who truly love us (yes, even God) I think we would all cash in.
I know your present situation is absolutely tearing you apart. You can't fix this, you can't make this all better and you feel hopeless. The hurt you feel in your heart is unbearable. And you're right, everyone posting now or have in the past has had their heart torn apart watching their loved ones suffer.
You don't want to hear that God knows what He's doing because it feels like a betrayal that bad things do happen to good people. But hear goes - - I do believe He has a plan for us. He did give you your precious spirit and it may bend, but I pray He will not let it break. You have a special purpose in your life right now. It is not for naught. I truly hope some day that you will be able to look back and be at peace.
Years ago when my Dad was in the last stages of CHF, the daily hospital visits were almost too much for me. I was seaching everywhere for strength and my faith was as low as it could possibly be. As I was taught at a young age, I started to read passages in the Bible and came across "give thanks for every thing". How could I possibly thank God for the devastation that was taking over his body. But I did. Everyday, on my way to the hospital, I would say a silent prayer that in the midst of this tragedy, we all would be able to give thanks for the good that would transpire from this. Looking back, I would not have changed a thing. My Dad's life truly had a purpose and impacted all those who came into contact with him, especially those last two years of his life. He was always my hero, my rock, my teacher, but never as powerful as those last two years. Through his suffering he was an inspiration to all. Especially through his faith in God.
Oh, I know this is so long, but I guess I'm trying to fill up you heart. I don't want you to feel despondent. I know I can't change your feelings. They are yours to embrace and I honor that. But, I will be praying for you Jane. That is one thing I can do. I pray that some day you will see that light at the end of the tunnel.