Taken aboard Nihilus's ship, she awoke to find that the flesh where her eyes would have been had been removed. Distraught, she sought out the Dark Lord, questioning why she alone had been spared.
Fractured and vulnerable at best, overwhelmed by the dark power surrounding him, Marr allowed Nihilus to take her for his own. In an attempt to make her believe in his cause, Nihilus showed her a vision, forcing her to see the galaxy in a way that her people never could; sentient beings on other planets, disconnected from the life surrounding them, unable to feel the Force.
The vision severely damaged Marr's Force Sight—which she, as a Miraluka, had to solely rely on, having no physical sight—and she became convinced that all life must die.
I found the above lines on Wookiepedia but they don't seem to make any sense? What did Nihilus show Visas?
And I believe that the Exile's reconnection to the Force sent out echoes which was the reason that Nihilus and Visas sensed her in the first place? Am I right?