Karin, sounds like you’re still trying to be the reasonable person intent on working out a mutual solution, and I’m concerned that this might be a situation where that could cost you.
Okay, now that I’ve said that.
If you feel you must meet with the “fiend,” then please do it in a building with lots of dedicated and highly-trained security staff around, such as your local City Hall, outside a police or fire station, in a big bank with lots of tellers, the lobby of an expensive hotel, or (if there’s one nearby) a really high-end jewelry store or at the jewelry counter of a high-end store. Station yourself so that you’re within the security people’s direct line of sight.
If it’s in the lobby of an expensive hotel, arrive early. Even if you’re not usually out-going, exchange pleasantries with every staff member you pass. Buy a snack or non-alcoholic drink. That makes _you_ their customer. Finish it before he arrives so that he’s not likely to get himself something at seeing the social cue of your eating.
If you can’t manage someplace with a lot of professional security staff, go at least for a place where there are some kind of security staff. A building lobby, anything like that.
And bring at least one friend. If the friend and you can both wear business or semi-business clothing, do so. That makes you look more “respectable” and sad but true, people tend to assume the better-dressed person is in the right if anything comes to a physical or verbal tussle.