Chic - you are doing so well, and yes you have a lot of life left in you. Think of the precious times with your grandkids, and how fast little Jack is growing up! How important you are to them and the rest of your family.
My one uncle is bipolar, his son is schizophrenic, and they both mooched off g'ma's social security when she was alive. My other aunt and uncle refuse to enable them, and they have learned that the cost of living isn't free. If they spend their $$ on weed, cigarettes and whatever else, they have food stamps. If they sell them, they don't eat.
I would make sure that son knows he can't just turn the Internet back on. I assume it's in your name, and I would make sure your carrier knows that NO changes are to be made without your verbal approval.
Let him try to get it on his own. He will probably find out what I did, credit was not good enough and dad agreed to cosign it for me, but it's MY bill.
I didn't appreciate the true cost of living until I hit bottom and went from making over $50,000/year to minimum wage, and I was older than your son.
Yes, he may get angry, he may try to manipulate you and he will probably do both. Hard as it is, stand your ground. You told him what he needs to do to get Internet back on, and since it's under your control, you can change the rules to add "now that you're working, the money either goes into a savings account that you can show me the balance, or it goes to bills that are due to keep a roof over your head".
I do have an idea of how angry he can get, how he can twist things around to where he makes you feel guilty. BTDT. bratkin has done the same with dad and though he sent her $40 last night, he told her "my van is broke and without it, I have no work, this is the best I can do". All this is from them not working, can't drive the truck as couldn't afford insurance, and taking out a title loan on her car, which she may lose.
I glad it not in a position to help them, so they don't ask. If I were? I still would not give in as I don't see them learning any lessons. Actions speak louder than words, and their words are gimme, gimme, gimme.
Bratkin and I lived in the same house for 6 months and did not speak as I was tired of her selfish and drunk behavior. She tried to pick fights, I walked away or took off in my car. She finally told dad "I think I need to change my attitude" and she did, and we get along well.
I know you don't want to leave your angry son in your house, as he may do damage. However, you do have the right to say "this is my house and my rules. Don't like it? Take a walk and think about it. Now."
Scary to do it, but darned if it didn't change things when I lived in dysfunction junction, though it wasn't my house, I would still distance myself.
You can do this, you've already made some amazing steps forward. You also have a ton of support here, and I have no doubt you will find some more f2f support. So very proud of you!!
Hugs and prayers,
Amy