I wish you could arm yourself, it's terrible that you are faced with a situation where your government is unable to protect you and simultaneously disallows you from protecting yourself. I don't know about UK laws in regards to Mace/Pepper Spray/tasers? Any of those things??
Self defense classes are good to take but don't rely on them. If you do I don't suggest taking one specific style, if anything find a good MMA gym near you and keep practicing regularly. MMA takes the most efficient and effective parts of any type of fighting style and puts it all together without the stupid rivalries and loyalties. Someday you might be proficient enough to react but this is a long term solution and you have an immediate problem.
Edit: A basic womens self defense class is a good place to start to get good at the basics.
Then they went on to show and practice basic self defence for if attacked (eg from behind). I was quite suprised by how easy it was to learn quite effective techniques in such a short space of time. At the time I was in a job that occasionally involved conflict situations in which I was threatened and it really helped increase my confidence in dealing with them.
I hope you find something suitable. Re the unstable person, it sounds like they may fall into the danger to self/others category. Is there anyone you can express concerns to eg their GP? Stay safe xx
© 2021 MyFitnessPal, Inc.