A huge congratulations for leaving again, OP. It was a mistake to go back before, don't make the same mistake again (note also how his behaviour escalated after you went back, because he knew then that you would put up with everything he had done before and so was comfortable to push it even further - if you go back again he will get even worse).
But when he's sober he is genuinely a completely different person and I know he was trying so hard before and showed he could be really great and I know he could do that again and I really want that.
You seem to think it's very meaningful that he is not abusive all the time. It's not, no abuser is abusive ALL the time because if they were it would be much easier for their victim to flee. Google the cycle of abuse, this is what you are experiencing. The fact that his abuse escalated while you were pregnant only means he is a typical abuser (they get worse when they sense that you are more vulnerable and/or less able to leave), it does not mean that he will ever go back to pretending to be nice all the time. Abuse always escalates, it does not get better.
My dad has never been in my life and I'm really sad about that and I want to do everything I can to help him be a good dad and I know he can.
This man shouldn't be in your daughter's life, as you have recognised with your concerns about him seeing her now. The way to avoid this is to make external agencies aware of what he is like. Ring Women's Aid (it's often easier to get through to your local branch than the national number, have a look online) and follow their advice. There are ways to prevent him having unsupervised access to a vulnerable child but you will have to be honest with people.
I don't think he's abusive really, I mean lots of people are angry when they find out their partner's breaking up with them and think strange things.
He did not only behave abusively when he realised you were leaving (although, again as is common with abusers, he did escalate at this point). He was violent and sexually assaulted you well before that.
And he is an alcoholic yes but he doesn't mean to hurt me its not really a conscious thing, he's not like cruel or mean
He is the definition of a cruel, mean man. His behaviour towards you is extremely cruel and mean. Stop trying to make excuses for his motivation and judge him on his actions. He is violent, he has sexually assaulted you, he is verbally aggressive, he is emotionally abusive.
There are two options here: he genuinely can't help it (in which case you should stay well away from him) or he genuinely can help it (in which case you should stay well away from him).
I'm so sorry that he is this way, OP, but you can't do anything about it. As AlAnon will tell you, you didn't cause his behaviour, you can't control his behaviour, and you can't cure his behaviour. All you can do is save yourself and your child.