I cannot help you but i had an upstairs neighbor years ago and every night for hours you could hear water being run or flushed and i mean 5 or 6 hours in the evening. Also this person walked across the floor in shoes again for hours didnt even seem to sit down at all. It was totally bizarre they never seemed to sit down not at all. Id go to bed about midnight and they would still be at it. No matter what room i was in. We used to hear dragging noises across the floor and i can only imagine a chest but seriously how many times would a person need to do that. She was the weirdest neighbor we ever had and we were never able to work out what she was doing. Try not to let it bother you too much i know its upsetting when people are weird like that.