Come play my game and forget about revenge. The game has just begun so its a good time to jump in and have some fun.
Some of the advice you got here from others is very good and I can add one more thing to it:
When you have hateful thoughts for others, it is like a prison for YOU! It is like taking poison in the hope that the other person dies from it! It actually damages you the most. Let it go and free your mind.
I find that the easiest way to forgive someone is to find a reason why they may have done whatever it was they did that hurt you. You might not agree that what they did was just or proper, but by finding a possible reason, I found it much easier to understand and thus forgive. That frees my mind and sets me free.