When you love someone unconditionally, no matter how much you were hurt, you could never be mad for long.
You sincerely wish him nothing but happiness despite what he did. Maybe he is not fated to love you but you do hope the other girl is worth it. Just as long as he's happy with his life with or without you in it. Angry and weak at first but as soon as you let go of things, you gain your peace.
By way of contrast, lust is a completely different thing. It's an initiation in every kind of feeling. If he broke your heart in this stage, you might wish he got his damn Karma. May he got broken worse than what he did to you. Karma is a bitch and it chases like wildfire.
I've had both. The latter one is a quick-recovery, yet torturing with jealousy. So pray hard, may he be served what he deserves.