Oof! That sounds like an unpleasant situation all round, Molly.
I think that Rosie's suggestion that everyone knowing that the transman is a woman and the transwoman is a man is the best way forward. That way, people will learn to accept transpeople as transpeople, and a lot of the pain will lessen. The more of that sort of thing the better, so long as it is handled sensitively, particularly at first.
Eventually, it really won't matter how people 'present', but nobody can claim to be the sex that they aren't, and the language will reflect that. I hope.