I can see this from both sides. There is nothing wrong with wanting to sleep over with your boyfriend. On the other hand, there is nothing wrong with him not wanting you to sleep over. I think he probably does see it as a next step towards greater commitment, and he is setting a clear boundary with you and saying he is not ready for that step. That is his choice and I believe it should be respected. Not everyone wants to move towards greater intimacy at the same pace in a relationship.
It was condescending and belittling for him to refer to you as a child, whining for a toy. However, is there some truth to that? As an adult, you told him your desire to sleep over. As an adult, he set a boundary with you and told you he was not ready. How did you respond? Did you respect his boundary and his right to make it as a mature adult would? Or did you keep pushing to get your own way regardless of how he felt, as a child would who cannot take NO for an answer? It is his apartment and it is his right to invite others (including you) to stay over when HE wishes.
Of course, if you don't like the answer you get, and you feel he has OCD and is trying to be controlling, you are free to either wait for him to get treatment and come around to your way of being or you can move on and find another partner who is more compatible with you and more willing to welcome you into his heart and his bed. I think turning the issue into a power struggle between the two of you, as to who is going to be the one to get their way, will be detrimental to the relationship in the long run.
Cog