Am I a rebound?

Hey twoX, thanks in advance for taking the time to read and input. I have been in a relationship for six months and things are going really well. I am in love with him, he is so good to me, and we are making plans for the future. I have one problem, and it's somewhat self-inflicted, but I still need advice. Before we were together, he was with someone for eight years. They broke up not long before we got together and I feel like I may just be a rebound to him. He has done nothing to make me feel this way, and the timing of it is the only indication. We have talked about their relationship and he says it was dead for about a year before either of them wanted to officially end it. As I said, we have been together for six months now and I really care about him. I don't want it to end, but I am afraid that if he doesn't take some time to himself, he will never be fully ready for our relationship. Any input or advice is much appreciated. Thanks!