Limbo

Here we go...Monday again. The start of another week of phone calls and trying to get my son out of bed. He will sleep ALL day while I deal with all the realities and then be up ALL night while the world around him sleeps. I can devote my entire day, as I have done so many times before, trying pointlessly to wake him up....he is out cold.
Social workers, Family Support, Drug Centre, all want to know why my son has not been attending appointments.
Well, now that he is 18 I seem to get very little useful advice from all the various agencies besides "kick him out" or "call the police". Yet I am the one who wants to help him....so frustrating!
How can a person try to change another's self destructive behaviour into productive behaviour? He is 18, but still my child and I want to help him though at times I despise what he has become. However, having said that, I have two younger children who I need to protect and take care of as well.
I am forced into feeling that I have to choose between my children while we just get pushed around from one service to the next.
Has anyone else been in this situation? Any thoughts on how to get your teenager to "see the light" and start making positive steps to change? How bad does it have to get before he sees how serious this situation is?