Believe it or not, most of the time I can tell reality from not-reality, and I still have to deal with the not-reality experiences at the same time, while knowing that they are not real. You can experience something as though it is real, while knowing that it's not real. This is my most common state, as it is the "in between" phase between total lucidity and completely slipping into psychosis, the phase where I can and do still reality test effectively. But I also have to reality test, so it's still a struggle.