Er...you can die coming off methadone.
He has an opioid addiction...no one dies from going cold turkey...suck it up cupcake and put up with the sh!t you're going to go through.
If that sounds harsh ...stiff sh!t, I watched friends after the Vietnam fiasco with habbits longer than your arm go through withdrawals and come out the other side.
There us no such thing as an ex junky...you're just a junky that hasn't scored yet.