I am a Ms. Have been since I first heard of the term in the 1980s and have kept it ever since. Single, married and (happily) divorced I have remained a Ms.
To me, it seems like such a sensible term of address - men are always Mr so why not have a single term for women too? Do we really need to know the relationship status of a woman before addressing her correctly? No, of course not. If I'm writing a letter or email to a woman and I don't know which form of address she uses I automatically opt for Ms. It's simple, and it means she could be married or not.
Many people think that by having the title Ms that I'm a raving feminist, and they'd be partly right. I'm proud to call myself a feminist and don't see it as a dirty word. I'm a feminist but don't rave on about it. I just happen to view equality as a right, not something to be embarrassed about.
I have a (male) colleague who really emphasises the Ms when he addresses me in school, turning it into a Mizzzzz almost as though it's funny in some way. Whatever. The children usually call me Miss and Mrs (as they do with all female staff) and I don't make a big deal of it, but occasionally when they ask me what Ms means we'll have a little conversation about why I use it. To them, it's not a problem and neither should it be.
In my early 20s I worked in a male dominated industry as a project manager and remember being asked to leave a meeting at a car company because 'this is a male only meeting'. I sat in the corridor outside the meeting room and my colleague, a man, had to keep coming out to ask me the answers to their questions. Can you imagine that happening these days? No, and quite right too.
I'm glad my own daughters won't be exposed to that sort of discrimination in the workplace, and while things are far from perfect it's still miles better than it used to be. My girls, who are 12 and 15, see equality as their birth-right which is a massive change from I was their age. I still remember when single women couldn't get a mortgage without their father's approval, and it was considered odd for a woman to keep her own name when she married - even though it's tradition rather than law that dictates it.
Don't get me wrong, I have no objection to other women using Miss or Mrs but Ms is a perfectly acceptable alternative and we should be free to use the one we prefer. So, which one are you? (Apologies to any men reading this, but I don't suppose you use any of them).