@mietze Everyone looooooves to tell you what to do in a situation like this (obviously). There's lots of "this is what you should do" pretty much everywhere you turn the moment you indicate there's something like this going on. What I will say is that the victim's advocate for my local police was, out of everyone and everything, the ONLY person with advice that ACTUALLY helped. They have professional training in matching up situations with the right resources and steps to take, rather than just throwing things at the wall until something sticks.
ETA: I will add for the other folks reading this, sometimes it IS okay to let the offender "win" by walking away and letting them have their way and not fighting, because safety/survival is a more important goal than the principle of the matter. I was instructed to let several of my activities go because it was not worth putting myself in danger over. It was recommended I find a different job, because my ex husband knew where I worked and had displayed a willingness to show up there.