If it comes down to have to decide between her and Halsin, I would keep her, since she would die without our help - or become a thrall again. Halsin can just go home and live his life. So in that case, the morally good decision would be to help her and hope, that you can help her see the errors of her way, I guess.
Metagaming would be me trying to get rid of Halsin. If I don't like Minthara after she is freed from the Absolute, she can become the new Orin bait.
