I remember my mum running herself ragged, looking after her elderly neighbour, though she was also elderly. She did her shopping, collected her pension, cared for her when she was ill, and often made herself ill, too, with stress.
The neighbour had several nephews and nieces who rarely visited. When she died, rather suddenly, they descended on the house almost before she was cold, stripping it bare. One knocked on mum’s door. Not to thank her for all her help, or offer her a momento, but to ask if mum had any of her neighbour’s pension money! She was really distressed at their cheek.
I have had mostly the same neighbours for 50+ years. We keep a friendly distance, knowing that anyone will help, in an emergency, and enjoying a chat if we meet. We rarely enter each others’ houses.
It’s sad that you are feeling so put-upon, nellgwynne, and hope that the helpful suggestions on here will teach your demanding neighbours to respect your boundaries.