I completely agree with Amy and the others that you're only going to get closure from yourself. I don't think it's a good idea for you to spill your guts to him now. If you do that, you'll be waiting for some response from him... so basically, you'll STILL be depending on him to make you happy inside. Don't depend on him for your happiness or self-worth anymore.
Besides, what do you really expect him to say if you lay it all out for him? What would YOU say, if someone you dumped a year ago suddenly reappeared and told you how you had made his life miserable for the past year, etc? It sounds like you want more than just to express your feelings. I mean, you just did exactly that on this board. You want to say this stuff TO HIM, and you probably want him to respond in some way. If you do that, you're counting on him, which you don't want to do anymore.
You're putting him in a position to once again break your heart, if he doesn't respond the way you want him to.
For a while, you need to be depending only on yourself for your happiness, not on him or any other guy.
I know it sounds really hard to find closure within yourself, but I've done it before, and it really is the best thing and probably the only way that really works. You'll find a way to let it go.