DH and I have been together for 17 years, married for nearly 14.
I think in that time he has lost a lot of the 'status anxiety' he had when we first met and dropped other attitudes he'd perhaps inherited from his mum who is something of a snob and assumes everyone is as judgmental as she is! He sometimes early on in our relationship seemed to get a bit nervous in social situations that I was making the wrong impression on people and being 'too shy' (his mum saw shyness as a terrible sin). It annoyed me but I figured he was just projecting his mum's issues and used to tell him when I thought I was doing just fine thanks! Thankfully he got over that fairly quickly.
He's also got better at managing his temper - he comes from a very shouty family, but he has got way better. He says he credits me with that, which is nice. I never 'took him on as a project to improve' or anything, and I dealt very poorly with his anger initially (getting upset, grovelling, silently fuming). But I think firmly standing up to him and staying calm has taught him there's another way to deal with these feelings.