Cut all ties. And hope he becomes obsessed with something else. Hopefully not someone else (poor them), though it is most likely it will be a person, a woman. Poor her.
Are you really friendly with his ex? You might do well getting together and discussing what you've both been through. Though my guess is that the thought of you two getting together would drive him mental.
It's abuse. Control. You know that.
The further away you get, the better. The less contact, the better. Really, no contact. You know, by now, that if he makes hurting and damaging you his "project", he'll give it his all. So just get out of his horizon.
This is why a. one should always listen to what the ex says about a partner, and just bear it in mind and b. it would be great if people came to us with "references" from their exes.
One of my friends gave me some good advice, once, which I shall pass on for anyone reading this:
- When you're embarking on a relationship, try and find out how the last one ended, with special reference to the "how". How did this person you're now seeing handle the break-up. It can be telling.
- If you argue, it's not so much the arguing, it's how you/they handle the argument.
Poor you. He sounds like a bad experience.
I know why you're banging on about how you're all professionals: You can't reconcile how someone who is trained to be analytical and aware can have found themselves in such a clearly abusive situation. It confounds everything you know. You know, he knows, that people have rights and should not abuse one another. He probably even says that.
You know, he knows, the warning-signs of abuse, and what to do (run!).
Well, it's a sad truth, but it happens. Mainly to women, and in spades when a woman is delivered (by the way society is structured, post-children,) into the hands of someone (mainly men) who doesn't rigidly adhere to the boundaries of another's autonomy. At least this happened before you were married, or had children, or something. Not that that stops this happening to unmarried women, and childless women. Just look at stalkers ... .
So, it happens. To many, many women.
It's crap. Actually, it's a disgrace.