Sane people can fall victim to various forms of addiction too though. I'm not saying he is a psychopath, I agree that that statement was a bit much... but just because he's not crazy does not mean he is not cold, cruel, and selfish.
You say he cares? About what, other than his dog and his money? Clearly not you, or else he wouldn't be disrespecting your home and your family... I don't care how many times you tell me he respects you; if he really respected you, he would not be stashing drugs in your home, sleeping with his clients in your home, and he certainly would not be putting a knife to your son's throat in your home. Those are not acts of respect; they are acts of disrespect. Period.
We all understand your desire and need to think of your son as your son; but as long as he is doing the above, and probably far worse, he is not the person that you seem to want us to believe that he is.
Here's the thing of it: We don't have to agree with you about your son. You don't have to agree with us either. But every day that you wake up and make a conscious decision to not respond to your son's behavior in the harshest way possible is a day that you have allowed him to behave this way, if not enabled him. As much as our instincts tell us to love our children and to protect them, you are not protecting him at all by keeping him out of jail. You are simply prolonging the inevitable, and adding logs on the fire so that when he does get arrested, it will be even worse than it would be now.
Is this post a tad bit harsh? Possibly, and if so, I'm sorry. Is it excessively extreme? I think not. What is extreme here is the situation at hand, and it needs to be stopped while everyone involved is still alive.
I agree with Elizabeth too... you are not a bad mom. My mom is not a bad mom either. But that doesn't mean that either one of you does not need to pull yourselves out of this denial that you're in and get the help you need.