Sit down and have a long and loving talk. Make sure that he knows that at this talk (or talks) there is a safe place for him to say exactly what he needs to say without any punishment after. Ask him how he have it most of the time - and not in his fantasy world, but in the real world. Is it too hard on him? He can wish a really hard dominatrix but in reality not be ready to live it and so on.. Do he have any ideas that would make it easier for him? Sometimes it is necessary to take a step backward before going two steps forward. Hopefully, it is not a sprint you guys are doing but a marathon that you can keep on doing without burning out in it. Well I could keep going, but I think and hope you get my point.