Loads of good advice above. So sorry for the situation you find yourself in.
Things I would do?
I would try and get a number of family or other visitors to pop in and out very regularly or come and stay, especially any male relatives.
I would try and have assertive confident body language, shoulders back, head high, smile and look happy (even when I feel totally the opposite)
I would join some local organisations/ WI/ coffee mornings, clubs, activities where you have a common interest with other locals, anything going on in the village and get some new friends on my side.....and quietly listen, you may be able to glean information.
I would regularly invite different people back for coffee and a chat - to be seen, to have a presence, that it’s not just you and your partner living there. Take up your space, don’t appear apologetic, that sort of thing.
Give the impression of “busy”
If there is a PCSO can you quietly befriend them, get them to pop in for chats....that’s another “presence”...and also your nasty neighbours won’t know why the police are actually calling....
I travel a fair bit and have observed other nationalities and how they deal with grating behaviours and things (which I am now learning from and copying!)...for example if people are being passive-aggressive/loud/intimidating/overbearing in someone else’s space - I saw the best reactions were from people who carried on looking happy, reading their newspapers, having their own conversations and just pretending they weren’t there, not acknowledging them in any way. The intimidating people want a reaction, so they get frustrated when there is none ?
Hope things improve for you