This happened to me last year. I got divorced and thought it would be a good idea to live with my mom and help her out with her bills a bit, and wait out the sale of my house.
She made me insane. We get along fine living apart, but I could not deal with living under the same roof as her. My solution was to go out and rent an "executive efficiency", basically an apartment that is furnished and all utilities are included, even though it is tiny and meant for short stays. I stayed for 3 month lease and it was fine. SO much better than being under her roof, that's for sure.
You have to at least have a room you can go to. No? Go there and listen to the quiet. Use earplugs if it's not quiet. If that doesn't work go out alone and spend time enjoying some shopping or doing things that you have been needing to do. Just do it alone! Sometimes we need to take some space for ourselves. The best thing would be if everyone had something to do one night. They'd go out and then you could have the house all to yourself to enjoy the quiet.
Perhaps you may even look into moving into a place where you can be left alone as some people are very content that way.
Light a cigarette I guess lol
Just tune them out...go hide in the bathroom for a while...I do that when i am over at my grandparents house...fake read the newspaper...or a book...go out for a stroll , call a friend....fake call the office outside...run any errands that require you to go out
Oh ..good luck!
Keeping your distance would be wise. Not for their sake, but for yours. Good luck!