Mia, I do understand the fear about his behavior being unpredictable, but that's all part of the crisis/depression. They change and act out because they can't cope with life and they are miserable inside. You have to try to look at him as a neighbor or a distant relative. He's not the man you knew and you have to accept that for now. It's going to take a long time before he settles down and figures things out.
BTW, they like to control and manipulate the spouses. Threats are one way of getting you to do what he wants and when he wants. It's also a way to get you to back off of him.
You have nothing to fear but fear itself and he knows that you are scared of what he might do, so he's going to escalate that fear to get you to do what he wants. When he sees a calm, collected and self assured woman who doesn't react to his behavior, he just very well may stop some of his threats. You'll notice he'll try to be nice and then go back to being Mr. Nasty. It's his way of keeping you right where he wants you...in a corner shaking w/fear. Don't allow this man to scare you. You are a grown woman who has a lot to offer someone and if he's that darn stupid and can't see the many qualities that you have to offer...shame on him.
Now, off you go...get out of the house for a bit...even if it's just a walk. The fresh air will do you a world of good.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.