I guess you have to think about your overall vision for your life, examine your sense of self, and consider whether he could actually change. If you tell him that you think he is so selfish and childish that you are considering splitting, it might get his attention so he can start a process of improvement, but only do that if you really do mean it. Divorce can't be a threat hanging over a marriage all the time. On the other hand, if you aren't clear with him about the problems, you can't expect him to get it. Personally, that level of immaturity would be a problem for me. Now that you see it, it will be hard for you to overlook it.