Even as a professional interventionist with a long-standing track record of success with other people’s families, when it came to intervening on one of my own family members, I found myself in the same position you might be in, trying to wrench other family members around to my viewpoint which I was certain was the correct one.
Different people have different viewpoints, different personal truths about how they see things. What I try to do is find some common ground for everyone. For example, not everyone may agree that Johnny has a heroin addiction, or they may not agree that it’s as bad as you say it is, or that it warrants treatment, but any family member of John’s would be hard pressed to disagree with the fact that overall, if you took a big slice of John’s life and looked at it, that he hasn’t lost his way. Drug addiction or not, does he operate well? Is he ethical? Can he be trusted?
This argument is easier to make. A good program doesn’t actually address any specific drug, it addresses the person; in any event, don’t let someone else talk to you in a compromising your own integrity. Simply because you respect someone doesn’t mean they’re able to confront the problem. Parents often have difficulty seeing what’s right in front of them because admitting their child is off the rails means their parenting was inadequate, that they failed in some way. So whoever it is you’re trying to help, don’t fail them.
“Every passing minute is another chance to turn it all around.” ~ From Vanilla Sky.