Jace has left. One day he was smiling, and the next he left a letter to Clary saying he had left…

My dearest Clary,

I remember the day we met. It's impossible to forget. You were impossible to forget. From the moment you stepped out of the pillar and stood up for the demon, knowing that I could have killed you, I knew that you were the strongest and most fearless person in the world. Nothing could change that. You made me feel, and while that hasn't changed- I swear -I can't keep living a life where I constantly feel that I don't belong. For the past five years, I have lived through the torment, and I may not tell you why I left, or where I am going, I just want you to know, that I am hurt. You hurt me. I thought you were the one person who couldn't, but you did. If it were up to me, I would have talked it out with you, be the brooding and non-emotional person I am, and face it, saying 'I don't care' and that the whole thing would be over. But because of you, I do care. I see that I am truly not the man I once was, and sadly, not in the way you want me to be. I am a coward. And the one person who could truly make me believe that proved it to me. I only wish I could be what you need like you were for me. I wish I could be what you were once for me: My confidant. And I know you will survive because you have been doing so for the past months...

And I know that if I see you, there will be no way that I could choose to leave, and I can't choose because you have already chosen it, so I am telling you that you may have repaired a broken boy, only to have broken it again.

Thank you, Clary,

Yours forever, Jace Herondale.

I, Jonathan Lightwood Herondale, hereby, resign my position as the Co-Head of the New York Institute, leaving it completely in the possession of Clarissa Adele Fairchild.