Honey,
You really need to get yourself to a Center of Excellence (COE), for your treatment, if the dr. is telling you that half the people die after SCT, then he is probably referring to his experience, and not what reality is with today's statistics (run don't walk away...) Find yourself some experts...
Many advancements have occurred in the last decade in BMT/SCT, and many factors go into accessing your final risk:
Age
General Health
Support group
Transplant team
Donor match (do you have siblings that might be considered a match?)
These are just off the top of my head, do research on this forum, and you'll learn a lot...
I too am 45, and if my odds were 50/50, I'm not sure I would proceed with a BMT either (although I might)...
You can follow my progress here (there are many here with positive outcomes):
http://forums.marrowforums.org/showthread.php?t=3792
It's won't be a smooth road, but if you line up the correct path, odds should be in your favor...
God bless...
__________________
Married, father of three daughters; now 46; diagnosed w/ Major form MDS 6/18/2013; had low counts across the board; Multiple chromosome abnormalities; Finished 2nd round Dacogen 9/13; SCT - Oct. 31, 2013; Sibling match 10/10
; 5.5% blasts down to 3%, now 1% (post BMT)