Do you have your own outside door to the apartment or do you have to come and go through their space?
Could you continue to be as independent as you obviously were before you moved into the flat?
I would focus on my life as much as possible and not get involved on a day-to-day basis unless required.
I hope things settle down once you have made a new life for yourself. 
It sounds like a huge adjustment to be truthful for all concerned.
Good luck.
Locked room for breakables when grandkids stay?
What do you miss from back in the day?
