How did you feel (vent)

So I'm expecting my third child from my bf. I have a 1&2 year old both from my previous marriage. We've been living together since I was about 2 months pregnant. my bf use to spend every other weekend with his bestfriend who he calls his brother and his niece. We loved two hours away. So when I wouldn't come visit he would go with them. My problem is when we moved he stopped going to visit then. I tried to get him to go visit my girls love that little girl (his, niece) he wouldn't go.his best friend started to like slacking. Not going to work and my bf always felt like he had to keep an eye on him well I asked if he felt like it was his fault for not being around he said no. well now since we moved I felt like he loved my girls as his own you know and they call him "da" I make it clear he's Andrew and he's not they're Dad at first we tried to avoid it but, they don't understand it. . . .last night we got into an argument I went for a drive with my girls the entire time they were crying for him. We came home and I found out he texted his best friend and said how much he missed them. It made me feel smurffy my girls and me were missing him but he didn't really care to miss us. Before we moved in I felt like that like girl meant more to him then anyone. When it came to my girls it was like "my, niece this, and my niece that" and his phone is filed with pictures of her. I have always felt like that little girl meant more to him then my goths ever would or even his own baby which is another girl. I don't know if, I'm over reacting or what I just feel like me and my girls aren't enough for him. That this baby won't be either. I feel like to him that's his family, not me and my kids. . . .did anyone else feel this way? My family had expressed they're concerns for how they are worried when this baby comes he will treat my girls differently. I've always tried to reassure myself it won't happen but I'm starting to worry. Has anyone else felt this way? We got into another fight today over it and I'm already willing to leave because I can't shake these feelings of not feeling god enough and the thought of my girls feeling the same scares me and breaks my heart. Please help.