This is a good start. in my opinion it does no good to always talk to him and to give sympathy to a situation of his own doing. I believe your son is around 30. He should NOT be bothering his sister who is in college or you and your husband. It in my opinion will help you greatly if instead of pitying him, which is what he wants, you start getting ticked off that he won't do the work to get clean yet he drags you into his messes of his own doing.
in my opinion 2am phonecalls are disrespectful. Again, I repeat you deserve to sleep. I would and did turn off our phones from 9pm to 8am. Kay could only reach us during normal hours. After a while we told her only one call a day. We weened it down further. She was in her 30s when we did that.
Sink or swim Kay has to live her own life and we have a right to live ours. You do too.