I'm so, so sorry to read that Big has finally gone to sleep, Chunti. His fight to live was just too much for him, he was so exhausted..
No-one could have tried more than you did to save him and I'm sure he knew how much you loved him .......he proved that by waiting for you to wake up so that he could 'say' a final goodbye to you.
Many of us here can understand the pain you are going through right now, you think it will never end but one day in the near future you will wake up and smile at thoughts of Big ......... you will start to think of all the good days you had with him and gradually the gnawing pain will subside and you will be left with happy memories.
I share your grief today, you did everything in your heart possible to help ease Big's final days...
Take care (((hugs)))