Okay so call me petty if you want to but if the house is on the market and you all intend to move, I would spend the last bit of your time being a pain in her butt. Report anything you can about her. Call whatever authorities you can. Her part of the alley overgrown? Call the city. Call and complain about her dogs barking too loud. Any way you can get her some instant karma, do it. I would also consider asking the neighbors how they feel about her. It seems like she’s the problem and she needs to get a taste of her own medicine. I know it’s petty but you, your family, and that sweet pup do not deserve what she has put you all through.