You may be past the point of diminishing returns. There may not be anything left that you can do for your son. It seems as though you’ve tried to do everything for him and nothing works. He continually disobeys your rules and gets into trouble no matter what you do for him.
It’s very admirable of you to want to help your son and to want to ensure that he doesn’t wind up homeless. I can understand why you would want to prevent this. He’s your son and you don’t want to see him living on the streets. But you are doing this at the expense of the health and well-being of you and your husband. You’re doing all you can and it’s still ineffective. You are degrading your life to assist someone who may not be able to be helped, at least not at this point in time. You may have to make the difficult choice of letting go. I suspect that the help you are giving your son enables him to continually engage in problematic behavior. He may be bipolar but he is also an adult male who seemingly has no responsibilities. Has he never been forced to fend for himself? He’s probably never had to fully experience the consequences of his behavior.
I know what I’m suggesting may not be easy or what you want to hear but it may be the only correct way to handle this situation. Things may have to get worse for your son before they get better.
I would suggest that instead of or in addition to NAMI meetings, you and your husband consider seeing a therapist for guidance on this issue. It’s not going to be easy to change the way you interact with your son but it may be the only thing that saves his life and yours. If he won’t change his behavior then you must change yours.