I am so sorry. Firstly I would write a letter of complaint regarding the police and the manner in which you were spoken to, that will be yu taking back some control of the situation. Mention in it that you consulted the police regarding disposal of debris etc and that you feel that you are being harrassed by your neighbours and that the police did not act appropriately on their visit.
Is there anyone local you can talk to and who can help you figt your corner, maybe a relative or neighbour, as I'm sure it feels very lonely dealing with all this on your own?
Just keep yourself calm and well, and continue avoiding them and ignoring them whilst you deal with the matter of the police. Once they are off your back you can start to address other things. The council would be a good port of call as well. Hope things cheer up for you soon xx