The Shadow Of Tyr: Book Two of the Mirage Makers by Glenda Larke
Ligea Gayed has been lied to once too often. Now she has turned against her former employer, the secretive Brotherhood of the Tyrans Empire, and must evade Favonius and his Jackals while also recruiting others to fight with her.
Yet, despite her best efforts, a rebellion is hard to come by. Except within her own family, of course. Ligea's son, Arrant, is prey to feelings of inadequacy, and is angry about his mother's relationship with a man who is not his father. Unable to accept what is happening to him, he becomes susceptible to the blandishments of his mother's enemies. Worse still, in the middle of a war he is a Magoroth unable to control or use his power in a constructive way.
In seeking to punish Ligea for her relationship with Brand, Arrant and those around him might well lose everything . . .