Blooker, I don't have much advice for you, because in the end it will have to be up to you to get over this mess. Eventually you will, everyone that doesn't kill themselves does; but it will have to take time.
My advice is: don't dwell on the sad stuff. In fact get as far away from it as possible (except for you dad, patch things up there ASAP). Also, whatever sad feeling you have right now, you need to get that out of you. The only way man has found so far is through art, sport, or violence. I highly recommend the first two and strongly recommend staying away from the third. Whatever you do, just make it big and make it scream out what is inside your soul.
You are loved, even by your dad. If he is sad about what he did to you, it makes it that much more obvious. Forgive him, but don't forgive your ex. Love is weird and it is very painful once over; but you will be stronger after all of this, I guarantee it (so long as you don't kill yourself, of course).
