How do you get an 18year old into drug/alcohol rehab?

Our son needs help, but won’t admit it – won’t go.
He feels we are the problem. His life is spiraling downhill so quickly – and we are very worried about him and his future. Even counseling would be acceptible. Has anyone else experienced this with their teen? How did you get them to realize they need help, and get them to go. It would be much easier if he were 16 or 17, but he’s considered an adult. Serious responses only please. Thanks!

More Meth Drug Addiction Info: