Bhavna,
My heart aches for you two. There are miracles that happen everyday. There are folks walking around today that were told they wouldn't be.
I know it hurts when folks say things like everyone has to go sometime. No one can possibly begin to feel what you are going through.
Hold your fiance' everyday that you can. That may be a couple of months of many years, only the lord knows how long that will be, but hold him.