How can I protect myself and the continuing thousands of dollars of damage he is doing on a daily basis to my property and my family and I?

I am afraid my neighbor will resort to physical violence. I will try to keep this simple. Boundary clearing - neighbor with no permit cleared 50 feet of my wooded property. Requested in writing neighbor obtain a border survey prior to further work. Neighbor hired survey done. The same contractor cleared two more times - this time intentionally crossing the borders (on two further occasions and causing damage of 18,000 sq. ft. (60 x 30) and loss of many native hardwood mature trees. He has been cited by code enforcement on multiple issues. Now he is intentionally 'killing' the border hedge that has stood for 28 years. His behavior is becoming more aggressive and damaging and I feel very afraid of violence escalating due to this 'deteriorating mental state' (many hundreds of documented photos and videos of the damages). I finally called the county sheriff department to report vandalism over 1,000 and they refused to even look at the case, calling it a 'civil matter'. I expressed my concerns about the deteriorating mental state, again dismissed. I'm scared, the cops are no help, I documented him (from inside the house) doing clearly odd and bizarre activities and focused on killing all the trees on the border. I'm scared and I don't think I can afford an expensive attorney because I'm on a fixed low-income. This is a terrible position to be in and I appreciate you listening to me.