I need help.

This is actually my first time posting on here. So to tell a little bit about me, my girlfriend is pregnant. She is going on 16 weeks and we both are very excited about having a kid. We have been together for almost 3 years. And had talked about getting engaged then married. Since about a year to 2 ago I had started treating her differently without realizing it. I honestly just didn't even realize I was talking to her like she wasn't a princess. God she is my princess. She is amazing and I am going to counseling to figure out how to talk to everyone better, because I don't like the fact that I come off this way. I just need some advice. We have had a falling out and she doesn't know if she is still wanting to be with me because of how I had been. I am really trying to fix how I treat people, but I don't know how to keep her here in order to show that I am trying and it's not just a false promise. I want to do this for the kid and for us, but I just don't know how or if I can win her over. Is there any advice or anyone that has been in this situation?