I agree with everybody here, with one exception, which I’ll get to.
Cry now. Make sure you don’t have any tears left when he comes back and tries to manipulate you again.
And he will.
Which is where I disagree, at least in part:
In my experience, the mother who’s willing to give up everything for her kid winds up, in fact, giving up everything. If you’re going to offer an “I’ll always be here” sentiment, it must come with conditions.
That’s why I say, Cry now, because if you’re going to do this you need to commit. Not just legally (pursuing the emancipation option), not just logistically (cutting off the cell phone), but emotionally. You’ve given him every chance. Something is wrong, but he’s the one who needs to figure it out and come to terms with it. You can’t live his life.
If the original door is open, even a crack, then there’s a chance you’ll let him come back through it. You need to close and lock that door completely. You can let him know there’s another door, but it’s a totally different one; it will come with a written and legally enforceable contract of expectations, including (I would suggest) psychological or psychiatric counseling, with a no-exceptions clause for immediate eviction upon the first breach.
If he does this, he may end up homeless. He may end up in prison. He may end up dead. But the life is his to lead, and the choices are his to make. If you leave open the option of returning without closing out the original emotional commitment, then one day you’ll come home and he’ll be gone with your television and your jewelry. (Which reminds me: Change your locks, too.)
So that’s why I say… cry now.
I feel worse for your situation than you can imagine. I’m so terribly sorry you have to be going through it. From some personal experience which I won’t describe out of respect for the privacy of some people I know, I can identify with your circumstances. That’s why I led off with the harsh real-world stuff above, and saved the sympathy for the end. You strike me as a smart, sensitive, and compassionate person, and you don’t deserve this shit. It’s a terrible thing when a son goes wrong. I’m so, so sorry it’s happening to you.
So… cry now, and let him go to screw up his own life. Otherwise he’ll take you with him.