I still have people write to me as "Miss XXX" after having met me, using my married name, which really annoys me. I have a huge diamond engagement ring and large wedding band I wear all the time, trust me, it's easy to see that I'm married.
Here, here!! DH and I got married at 21 - I used to be a school teacher... everyone knew I was a 'Mrs', yet I was always a 'Miss' to them - even the staff called me that when they were talking to students!