City of Ashes

Clary thought of Magnus, and of him not telling Jace the truth: that Alec did not want Jace to know about his relationship with him, because he was still in love with him.  She thought of the satisfaction it would have brought Magnus to say the words out loud, to acknowledge what the truth was, and the fact that Magnus hadn't said them-had let Alec go on lying and pretending-because that was what Alec wanted, and Magnus cared about Alex enough to give him that.  Maybe is was true after all: Love made you a liar.