I agree with the hospice thing. It's amazing the things that the addict will say to increase their chances for "help." MY son used the.."I am going to rehab" card in order to come and stay with us overnight (about 3 times) and never went to rehab. There was always "something" to keep him from checking in.
It's not that you shouldn't believe that he has weeks to live. It's very sad but really...there are options out there that won't compromise everyone's peace.