I will complement you on trying to work through his cross dressing and being supportive and participating. Not all ladies will do what you have done. While some Cd’s do not change their sexual preference3s while dressed, others do have a desire to be with a another CD or a man. In my opinion, that is a hard no line to cross. Which I do not think you are asking too much.
he needs to do some deep searching as to what he wants and what costs he is willing to pay / sacrifice with your relationship. PM if you want to discuss further