As a lifetime crossdresser with a tolerant wife I can tell you conversations are key. Like others have said boundaries are needed in every relationship! First your husband needs to be honest with himself, only then he can be honest with you. The questions put forward on this site for applications are a great place to start. Ask him the questions asked of you when joining this group. Discuss what he wants and what you can accept. This will open the door for the boundaries you both can accept. Mutual respect and love will heal the day. You should know he will never stop crossdressing, and he and yourself will be setting him up to hiding his dressing and lying about his dressing if he tells you he can and will stop, he might purge but will start again. The urge gets stronger as we get older.
My wife and I have set days of the week where I dress and we sleep in different bedrooms on those days. We have times we travel and I completely dress in fem and other times we travel as husband and wife when I only dress in my male clothes. When we travel and I’m dressing in fem, we travel as friends, book separate rooms and have no intimacy. When traveling as husband and wife we have a single room, king bed and our intimate time. When I’m dressed there is nothing sexual between us we are just friends as two females. A side note, I don’t pass but still dress in public, knowing I’m atypical, and not submitting to political correctness. I don’t have a problem correcting people who call us ladies when we’re out. I let them know my wife is all woman and I’m a man who likes to present as a woman. This is the part of being true to my self and true to my wife. She tolerates my dressing in public but it’s to places where we have little chance of being outed. Discussion is key and boundaries you both can abide to are key. As you go forward things can change as you both become more comfortable with his crossdressing.
Hope this helps,