Is my prayer valid and accepted in this house, in which impurity has been widespread for a long time, with my clothes that I sat with throughout its different parts? And is impurity excused if it has spread throughout the house?

Know that ritual purity is not a condition for clothing and place except for the performance of prayer. Therefore, if you intend to pray, then pray in pure clothing and a pure place. If the place is impure, and you place a rug or a prayer mat on it and pray on it, then your prayer is valid. Do not rule something to be impure except with certainty. Any place about which you doubt its impurity, its original state is purity. Strive against obsessive whispers (waswas) and do not succumb to them. It is permissible for you to adopt the easiest of the scholarly opinions regarding the transfer of impurity, to alleviate hardship.