Dear A.,
I'm so sorry you're going through this. It sounds like a really tough situation. A couple of things go through my mind, though.
How's his relationship with his father? This may sound goofy but bear with me -- I find boys need an "alpha male" to teach them, train them, and yes, to lovingly but firmly "boss" them when they are young.
Another thing you mentioned is that your son does no chores around the house. There is much, much value in learning to work! When we learn to work, we learn to appreciate. If I could suggest anything, it would be to make him 'earn' priviledges and freedoms, and when we fails to clean his room, mow the grass, take out the garbage, or dishonores his elders, he doesn't earn the freedom to go to ball games, get on the internet etc.
HTH!