Impossible to say whether calling the police was right or not, my mother called them on me once for something similar and it did push me further away but then my mother wasn't the loving parent you sound like and you clearly did it out of concern for him. Bottom line is however you handle a situation like that he's not going to thankyou so you have to do what you think is right at the time and accept that his thanks may come later when he's older and wiser.

I think that your son needs someone other than his family to talk to about his losses, someone who isn't emontionally involved, not on the basis of stopping him from using drugs and drink but someone who will look beyond that and focus on his feelings and help him feel positive about himself again, hopefully if you put it to him like that he will accept the support, I imagine from what you say he would shun drug councelling. He sounds like he's had an awful lot to cope with and we all want to be enough to help our children through there problems but often we're not.