Am I a fool for being with a man who still lives with his wife?

I feel messed up and need perspective. Greg and I have known each other for more than two years, through which time he and his wife were already 'separated' with the help of a counselor but still living in the same house. Over time we fell for each other and about 6 or 7 months ago became a couple when he said they had decided to go forward with an amicable divorce. They were just waiting for the best time to tell the kids (two older teenagers) and figure out who was going to move where. Six months have passed and no mention of a divorce. He says that there just hasn't been a good time to tell the kids. I don't quite understand this reasoning because he says he and his wife live in separate parts of the house, and while they are cordial and supportive, they don't spend time together anymore. Surely the kids know something is up already? Meanwhile I am a secret. His family does not know about me, I don't know if his wife knows about me or not- no one knows about us at all and I only get to see him perhaps one evening a week. I don't need a lot of hand holding and I'm not overly needy, but I'm starting to feel very depressed about the situation because it feels like our relationship will never grow. It can't. It's just stuck right where it was at the beginning. I never expected it to be easy or traditional and I expected that it would take time, especially where the kids are concerned, but I did hope that there would be a plan and something to look forward to. He claims that I am "The One" and we do have an amazing relationship. It has been my policy not to pressure him about his home life and just trust that he will figure things out. He says he doesn't blame me for being depressed over this and that it's amazing I can put up with it at all, but then it doesn't ever change. I am starting to worry that he's comfortable having his home life as it is, and then me at my house where he can be more himself. On the one hand, I can understand that need and I want to be there for him, but I also want to have a future and a partner of my own. Am I being unrealistic about this situation?