Argh! People who refuse to call you by the title you use are SO SODDING ANNOYING! I hate it!
I 'confuse' my undergraduate students by telling them to call me by my first name, and telling them my full name (which they can see anyway, on the website, etc). They're straight out of school and stumble a bit with calling me by my first name, ("sorry, it feels weird, cos you're a teacher!") but we're 7 weeks into the class and most of them have got over their nerves about it by now. BUT when they come to hand in essays they have to put my name and their name and the course number, etc. . . can you guess where I'm going with this?
Last time I got "Mrs Currants", "Professor Currants" and "Ms Currants" (the correct title, and surely the safest one? I mean, why assume anything? Ms is NEUTRAL AND THAT'S THE POINT! Damnit!). They know I'm married (though I don't wear a ring - pudgy preggo fingers not gone down!) because I've made a jovial remark or two in class about my teacher DH giving me a cold he brought home from school, so some assumed my surname was a married name. Nope! I quietly correct that part of their essays, and will be interested to see if anyone makes that mistake twice.
The idea that a married woman would be Ms was a bit alien to some of them, but I've been Ms since I had forms to fill in. Despite my whole family writing to Mrs DH'sFirstname, Dh's lastname.. . but they're just being bastards misguided like that. I suppose if they wanted to be formal they could use the fancy term for my job, 'Preceptor.'
Ooh, I think I'm going to insist on being addressed as 'PreceptorCurrants' from now on. On my gas bill... 
Can't wait till I'm Dr and can duck all this nonsense. Bet my parents will still write to Dr DH'sFirstname DH'sLastname, though. And if they sodding do, I'll ask them, pointedly, at what point they thought DH got his PhD...