Do they ever let you in?

Anyone wonder if your older child fosters or adoptees will ever consider you their family? We have a 9 year old foster to adopt son who has been with my family for a year. He's been in and out of foster care since birth (in 4 different states so time limits didn't seem to apply to him). There are tons of attachment and trust issues and I understand why seeing us as anything other than babysitters will take a really long time. He hasn't seen or talked with his bio parents in more than 3 years yet I can't imagine him ever calling us Mom or Dad or seeing us as his parents. I wonder if it's even possible. We've talked about the possibility of adoption since we are up to the goal change step and there are plans for TPR and we want him to assure him that we plan to be in his life if that's what the courts decide. He has said that if we adopt him he wants to keep his last name, he asks if he can still see his parents (which I don't understand since he hasn't seen them in years), etc. I know we are doing the right thing for him - he is cuddly and very fond of us but still tells complete strangers that we are not his family, only his fosters, and his family are x, y , z - a list of people he hasn't seen for years (including a half-brother that he he has never met). Luckily, he doesn't break out the story to every waitress or receptionist any more - just sometimes. I feel like he'll live with us until he's 18 but not really be a part of us. Anyone else go through these feelings? I feel a bit selfish and it won't change anything if that's the reality of it all - we've committed to being there for him and I will even if he doesn't think I'm his mom. But it would be so nice to hope.