VERY STRONGLY support.
Forcing someone who wants to die to remain alive is one of the most morally abominable things I can think of.
What makes you think the choice will only be made by the patient?
Hum... Because that's the whole point of assisted suicide?
I think "choice" is more complicated than you appear to make it.
Tell me, what is to stop an understaffed and crowded hospital or even a patient's own family from pressuring an ill person to just go ahead and die? I also fail to think of any viable mechanisms to prevent such an abuse.