Divorcing a drug addict

I need advice for a close friend (the husband in the relationship) who is in a really rocky marriage of just over one year.

They got married last summer when they found out that she was pregnant. She has always had a problem with drugs, particularly heroin. He smokes marijuana occasionally (allegedly because he is so stressed out about his life) and he's a convicted felon. His probation is about to end on September 15th. They have a baby boy, born this spring (whom I feel so sorry for). The husband tried to go back to school, and did OK last semester, but his GPA is really low from previous enrollment, and he is consequently no longer eligible for financial aid. He was working at a chemical bottling plant full-time and finally quit in July because his managers basically treated him like shit (since he's a convicted felon and they know he's desperate for work). Soon after, he picked up a job loading freight for a carpet-cleaning company, but that was temporary and they booted him. For the last week, he's been trying to sell kirby vacuums, but it's just not working out. I just called him, and he was in a Wal-Mart parking lot and was about to go in and apply for any job they have available. Nobody is giving him a second chance.

While he's out trying to make a living, his wife is sitting at home with the baby and she's doing drugs. She brings her druggy friends over and they shoot up or do whatever they do. My friend knows about it, but there is nothing he can do, apparently. He has to make a living. And when he gets off work, she goes out partying with her friends. Very recently, he got a phone call from child protective services that was very threatening. They told him if he doesn't get things straightened out, there will be intervention. And two weeks ago, they checked his wife into the psychiatric ward at the hospital. They never checked for drugs, though, I guess, and they diagnosed her with PPD. I'm not sure who checked her in, or all the details about that, though.

Well, today he's finally had enough. One of her friends died in a car crash and they're all going to do drugs tonight and party at his apartment. He doesn't want to be around for that, and he certainly doesn't want his kid around that, either. I told him to take the kid and call the cops on them when they're partying. It took a while to convince him, but he finally said he would do this (though I'm not sure if he actually will). I wish he had some family close by who would help him. There's really nothing I can do because he lives far away.

Does anybody know what he can do if/when he finally files for divorce, or if she finally gets caught and put in rehab? His biggest concern is that he will not be able to support himself and his kid without having anybody to babysit while he works. I really don't know what to tell him. The situation is so depressing, I wish I could do something about all this.