Entering a room without permission

Q: What is the ruling if the wife stays with her in laws in the same house, sharing all spaces like the kitchen, bathroom etc? Are the in laws allowed to use her bedroom as they wish? If she is not there can they sleep in the room and let other people in the room? The wife's possessions are still in the room and she is not informed of the people using it.

Written Talaaq

Q: A father of the husband while separated from his wife wrote a divorce letter which the husband signed and gave it to a third party.Some time later the husband decided to destroy the letter. Later on the husband and wife reunited. The wife had no knowledge of the letter and was informed of the letter only after she was reunited with her husband. Many years have passed by. Where does this marriage stand according to Quraan and Sunnah?