I know the threats and they escalate. My ex was never violent, but she likes to position herself to make herself the victim.
I told her that her veiled accusations I take as a threat and that is why I cannot be in contact.
I also know about being stuck with a life that is now over and they want to trap you in it.
They don't want you, but they need someone who will take away the fears.
Sometimes one-person isn't enough.
The way to do is, to not start to break down what happened and seek closure. I believe that was something I did wrong on reflection. Because you can't get that kind of closure from someone with a mental illness. You can't deal with their logic because that just causes more confusion for you.
I just kept moving forward with closing finances, how that works legally, step by step and didn't stop. I had to do everything, and she OMG put so many hurdles in the way. It took me a year to get out of our house. She had left me in. Documents that had to be signed I had to ask twenty times. Get the comments. I treat her like a child, I don't let her have space to do things she needs to. She trusted me and I did the wrong thing. Two months to sign a form. It was a long long process.
When he finds out you moved his stuff he might unleash on you. He will bring in trust issues and blame.
Have your message ready.
Without telling what to say. I would say.... I put your belongings into storage, so they are safe. I have paid for the storage for a month so that gives you time to decide what you want to do with them. Tell him how he is able to collect them.
I wouldn't put an ultimatum in there like I won't pay after a month or any comments like I wanted your stuff out of my house. Because he will latch on to that and only that. Then he will refuse to collect them to create a drama.
Keep records. Get your text messages into a cloud storage. Don't leave them on your phone. You have that phone taken there goes your evidence. Do not get angry, he wants you to get angry because that makes him feel better plus then he has something against you. Make sure someone you trust knows exactly what is happening.
I find the messages do get into their heads after a while. You just need to make them simple and not accusatory.
I told my ex that the most important thing is she is safe and I am. That I want her to be safe, to do what she needs to keep herself safe. We are not safe together and that is why I can't have contact with her. I think that sinks in. It's truthful and they have fears are about being safe, so they can relate to it. That is isn't my job to create that safety for her, she has to do it.
I wouldn't tell you to go to the police or not. I don't know.
After this contact. I would remove any way he can contact you. If that means changing phone numbers, do it. All your email addresses, all social media. I would advise anyone he can call to get your new details that he might contact them. They all need to have the same response for not giving out your details and prepared.
I would actually tell him you will not be contacting him anymore and to please not contact you in anyway again. Wrap it up in a nice bow. Have a good life, you wish him well etc.
Then you have a record. Then if he does anything to break it, you have something tangible to take to the police.