Actually if you listen to her comments in dark below an throughout kings fall. She makes several blatant statement about trying to stop crota before an everyone she was will basically dying in the process, she also states that she was being tortured by the witches in dark below. My thought process, they probably killed her ghost or mutated it/experimented on it, thus that green thing she carries is its altered light, then turned her tortured to into experimentation, an that's why she's got the third eye. The hive do have a relationship with the worms an host that much is clear in Kings fall, wouldn't be surprised if they had something to do with it. Either way she's half hive now, an the way I see it I wouldn't trust her either lol. Keep waiting for her to turn round an go all psycho on the people in the tower.