Has the apartment become impure, and what is the ruling on the prayer of one afflicted with obsessive doubts about impurity?

The cure for obsessive thoughts is to ignore them and not pay attention to them. The default assumption is that the prayer rug is pure, and it is sufficient to wash only the spot of impurity. The default assumption is that impurity does not transfer when there is doubt. Some scholars have gone so far as to rule that impurity does not transfer from one object to another if they touch and one of them is damp or wet. A woman suffering from obsessive thoughts can adopt this view and rule as pure whatever she doubts to be impure.