Since it's only been a short time since his divorce it may mean that he just got out of one relationship and isn't quite ready or is scared to start another one. He may have rushed into dating you so soon after his divorce and now needs time to himself which is what he should have done after the divorce it's always good to give yourself some time to grieve from the divorce and figure out what went wrong so he didn't make the same mistake twice. He may need some time to himself and wants you to be patient and wait for him to be ready and you have to decide how long you want to wait for him to be ready to start dating again. Even though he was legally single again he may not have been ready. In the bonds of marriage two people have become one and for some time it was only the two of them, it might take some getting used to being without the other mate.
Dating after a divorce is not the problem. The difficulty is the knowing when you are ready to date again. What really needs to happen are steps toward healing. And the first step toward healing is to take some time to reflect about your life and what you want from it. What I suggest to you is to give him some time maybe a few weeks to himself and then talk to him about whether or not he is ready to start dating again and if not then you may need to give him more maybe if he knows you are willing to go at his pace he may be more willing to continue dating. It has nothing to do with you so don't take it personal it's something he should have done after his divorce but he may have been too afraid of being alone and that is why he rushed into dating again.