Is this a healthy relationship?

I've been in a (granted, my first real one, and his first) relationship for the past 10 months. It was a one night stand that turned into something more, pretty much the next morning. Everything's been good and lately we've advanced to him having my key. In May I had separated from my crazy roommate (who basically would freak out if I had my boyfriend over more than once a week) into my own apartment, 10 blocks from where my boyfriend lives with his mom & brother. Since I moved 6 months ago, he's basically spent 6-7 nights at my place. Lately our pattern has been that we both go straight to my house after work, have dinner, watch tv, have and/or work out, and go to sleep. He's even got clothes at my house and the past few weeks has really only gone to his house to pick up some more clothes. I know pretty much everything about him, including his gross habits and quirks (farting in front of me, very lovely). It feels like we're getting super close, except that nobody in his life really knows about me. It's not that he keeps me a secret... it's more that he doesn't share anything about his life with anyone, ever. It's not about me, he does it with his job, friends, and family, where one aspect of his life doesnt' really interact with the other. I'm the only one that knows all about his life, not even his mom knows anything about him, not even where he works. He says he's always been like this and I believe him. But a part of me IS bothered by it, even if it's not about me, it's about him being secretive with every aspect of his life. He also can't tell me how he feels abuot me. He says I should know, because he's over all the time, loves spending time with me (we're practically inseparable except for work & Friday nights when we each do our own thing w/friends), and he helps me out around the house. Since he doesn't like to talk about his feelings or our future, we decided to discuss things on our 1yr anniversary (coming up soon!), and I think that's ok. But we've been getting even closer the past month where it feels like he's almost living with me, except not paying rent. I'm happy and satisfied in the relationship, but part of me wonders if it's really OK to go on like this... almost living together, very happy, but without him sharing his feelings with me or telling people in his life about me. I try to accept him as he is, because it really REALLY isn't about ME being a secret, it's about him being super-private and EVERYTHING in his life being a secret, but a small part of me still wonders.. is all this healthy in a relationship?