If the Master says he has no more use for her, and in fact just tried to kill her, does that mean he is reneging on their agreement, and that consequently she doesn't have to uphold her end of said agreement? That would definitely be a good thing for her.

I'm very worried about Gray now. I really hope Jack's friends can find him and save rescue him from the Wraiths before they can harm, or worse, kill hm. Jack would be devastated.