Man I feel for ya, those things are painful. Mine took a long time to heal. I know you know this - just encouragement as I also HATE going to the doctor, you should go and get it checked out. Best of luck - hope you heal well.
I like the wall idea but a simple berm of earth will insure it stays on her property.
If it is a down slope back to her it will return to the place from whence it came.
Sorry you got to deal with that, most likely code enforcement will help her with her problem, good luck.
You should have no bad feelings about that. I understand what you are saying. Fortunately it is a job seekers market and talent is hard to find. Money moves talent. Anyone you expect to make a move HAS to be offered more money. The deal is on them to understand that and if they don't then you...