She craves for respect within the dorm mates, she doesn't necessarily want to be more than them, but just the same. She wanted to be with people who respected her. But when Cheong ya severed that bond, she realizes she was just living a fantasy world where a person like her would have power. She was just day dreaming that there are people who may respect her. So she is ushered back to reality and reminded of her need for self preservation to take care of her father.
Her contacting the ansp to me felt like she realizes she has no allies within the dorm as well, since it was shown that her ties to the NK was false. And since she didn't experienced first hand the torture ms. Pi endured, she may not believe the atrocities of the ansp. That is why in EP. 1 she is a willing participant to help find the spy.
She may have sensed that she will be turned in for being a traitor by the likes of Hye roung. And so she contacted the Ansp to ensure that they will save her when the time comes. After her fantasy was destroyed she went back to self preservation mode.