My BF keeps me secret from his adult kids

Sorry, goofed that up Anyway, the wild child and her baby, who's named after my BF, were here this weekend and I had to hide everything I keep there before she arrived and while he texted me pics of him and the baby all weekend, he never called. I did what was expected and backed away like every other time. He called me this morning and we had the same discussion as every other time, what was my problem, he doesn't understand why this bothers me and I don't understand why he doesn't get it. He's said I'm the best thing that's ever happened to him, that he's waited his whole life to find me, he loves me with all his heart but I feel so marginalized and unloved everytime this happens. He says that he doesn't understand why it would bother me when he "spends time with his grandkids" and I've said repeatedly that it doesn't but I just never expected that it would be either or when it came to holidays and stuff. We've been together for 6 months and from day one everything just fit between us with the exception of this. His son is moving in from another state and will be staying with him until he gets established enough to bring his wife and kids here and the BF made a comment this morning that he hoped I understood that. I replied that it was different because his son knows that I exist and told his dad that he liked me. I'm afraid that this will go on for every holiday and birthday and I am starting to wonder if I'm the crazy one. He's said his daughters might be unkind to me and he's protecting me and "geesh, I've met his parents and his son and family, doesn't that mean anything?" Honestly, I'm not sure what it means, I just know that I feel bad and that he just doesn't understand why.