I've been here too, book :( You did absolutely the right thing to draw the line and call the police when you were threatened with violence. Do it each and every time your DS is violent or threatening to you. (You may not have to do it often: on the 3rd occasion my son kicked off, and I was scared enough to call the police, I also had him arrested and charged. He hasn't lost his temper since (fingers crossed), so for me it worked).
It took me a long time to get to this point - I put up with an enormous amount of verbal abuse and throwing things etc. before he got big enough and/or I got scared enough to call 999. It can take a long time to realise how bad things have got, when it grows just a little worse day by day.
This is domestic abuse. It isn't called that very often, and it's pretty taboo to talk about it when it's your child and not an adult doing it to you. But that's what it is. And it's more common than you'd think.
Do your very very very best not to feel guilty, and to feel confident you acted appropriately. If your DS catches the merest whiff of guilt, he will try to manipulate you. That's what people who are behaving abusively do. Your DS knows he is behaving badly - but he'll try to project his guilty feelings onto you if he can. I think it's easy for us mums to feel guilty in this situation, because when they're younger, we're used to 'fixing' every problem they have - and now we can't. But there comes a point in every young person's life where they have to take responsibility for their own problems. You can support them, but you can't do it for them. Your DS's behaviour is his responsibility.
As I said to my own son when things had calmed down afterwards: "You are bigger and stronger than me. I can't control you any more. If you can't control yourself, I have to call in reinforcements".
The stealing is another issue. You can control this quite well. Fit a lock on your bedroom door if you haven't already. Keep all of your valuables in there. You shouldn't have to, but it works, and if you give your DS repeated opportunities to steal from you (which I did - I speak with the benefit of hindsight here) you are giving him repeated 'practice' at abusing you and getting away with it.
You will feel very out of control. I know I do. And I am much stronger now than I was 6-12 months ago. But although you can't control your DS's behaviour, you do still have influence... You can keep on giving him 'moral messages' about what is unacceptable, even when you can't stop it happening. I have a 'stock phrase' I have used quite often over the past couple of years, which you may also find useful: "I can't stop you, but that doesn't mean your behaviour isn't wrong: you have to stop yourself".
Your DH's response is the subject of a whole other post. I am a single parent, so cannot be undermined in this way. You need his active backing. If your relationship with your DH is generally good, ask him directly for his support. Get him to read the chapters on fathers in Steve Biddulph's Raising Boys.
Keep coming back here for support. There are a handful of people who understand and who can give you some back-up :)