OP man to man as someone with experience in this same type of situation when it comes to family court let me give you advice on a personal level.
I'm going to save you a lot of pain later by just telling you the truth now. Unless you can prove that she is a completely unfit mother, your aren't going to win custody of a child that young over it's mother. It just isn't happening, at that age even 50/50 is a massive reach. If the child was elementary school age I'd say 50/50 would be very possible, a newborn it isn't gonna happen. It doesn't matter how much of a bytch she is, THE COURTS WILL NOT CARE. Even if you got 50/50 somehow they are still going to probably order you to pay some form of child support. That's just what they do to men, we get punished even if we did nothing wrong. This country hates and disrespects men, family court is the perfect place where it is on full display for you to see, you will get a reality check in that bytch.
As a man in family court you MUST PLAY THE LONG GAME. I hate to tell you this, but you are in a marathon. Your best bet is to resign yourself to paying child support, fight for your rights UPFRONT now, do not wait if you wait it will be even harder down the road, and DO NOT DO ANY THING BEYOND WHAT THE COURT ORDERS YOU TO DO(this is the most important thing a lot of men seem to not grasp, they let women make it hard on them instead of making it hard on the woman and that is why they never get custody).
If you have any other questions I can answer them, based off my own personal experience with this process. Just know this EVERYONES SITUATION IS DIFFERENT. You will be disappointed thinking your situation will be like everyone elses situation, because it won't be they are all unique.