I'm so sorry you've had to deal with a father like that, Freddy. I can't imagine the anger you must be feeling at the moment.
The one thing I'll say is this: other people's motivation is always going to be a mystery to us. For example my dad was always distant when I was growing up. I never really felt connected to him and thought he was doing it because he didn't like us kids. While certainly not being on par with what you experienced it didn't make growing up a joyful experience. I was angry and bitter at his treatment of us. Anyway, I had a drunken conversation with him when I was an adult and it turned out that he and mum fought so often about how to raise us in our early years that in the end he decided to butt out in order to maintain some peace in the household. He felt that it was the only way to maintain the family unit and even though it broke his heart he was willing to do it for us. Once I learned that my viewpoint of his actions completely changed and we're much closer now. Maybe your father had similar complicated motivations. If he was always consumed in his own misery, as you've alluded to, he could have felt too guilty to get fully involved in your life even when you reached out to him. Maybe he felt you were better off without him. It's sad, but some people feel that way.
Even if you never find out why he did what he did, being angry is just punishing yourself. Physically, emotionally and mentally long term anger isn't good for you. I've read on anger management sites that even just imagining a sympathetic reason for someone's actions is enough to defuse anger. And while it's completely understandable how angry you are maybe you should try and deal with the anger for your sake, not his. It won't wipe out his actions. It won't absolve him of what he did. All it will do is give you a small bit of peace in this situation.
Whether or not you get in contact with him is up to you, of course. You need to do what is best for yourself. He's made his decisions so he can't expect you to drop everything and come running now he's finally wanting contact. But don't avoid seeing him as a way of punishing him if it ends up punishing you too. You've gone through enough as it is. You don't deserve to make yourself suffer. The only positive thing out of all of this is that you may finally have a chance to reconnect with him like you wanted to in the past. Does he deserve the second chance? Hell no, but you certainly do.