Welcome to SR. The best thing I ever did was start posting here. So many people in the same boat. My son has been using for well over 2-3 years (that I know of). He currently is in rehab for the second time. The first time he was there was a year ago, and after the first week he walked out, went straight to his girlfriend's house, and then when she wasn't home, called me, and of course I came and got him.
Long story short, he left our house over 3 months ago, and was living with a friend and his father. Last week, friend took him to a rehab and he's been there ever since. He tried to con me into letting him come home this morning, but told him a week isn't long enough and if you sign release papers, your on your own. It's so hard trying to stick to your guns, but I know it is for the best. I hope he stays as long as they will keep him and as long as the insurance company will pay. Otherwise, I can't imagine what will ever become of him. He's still very manipulative. Good for you for sticking to your guns on this. My prayers to you and your grandchildren.