I think that RoseandJoan has a good point - I don't think there's a need to overreact unless he's said that he really dislikes your current look (and even then I'd want to figure out why and what it is). Some of it may be nostalgia or just him just making conversation, not something that has a great deal of importance to him. Even then, this is different for everyone and every relationship, but I would say if you're happy with your hair the way it is, then that's the most important thing.
Most men do seem to like long hair (except my dad - he's always preferred short hair, which is good luck for my mom since she's never had long hair in her life!). My husband does, and I know it. I've had long hair during some of our relationship and I may again sometime, but right now I like my hair short, I like how easy it is to take care of, and it's what I've chosen to do. It might not be his first ever preference for me, but he likes it well enough and he knows it makes me happy.
I do wonder about those women who have long, blah, always-thrown-in-a-ponytail hair into their 40s and 50s for the single reason that their husband likes long hair. Practically anything would look more cared-for and up-to-date than those non-styles, and honestly I think their husbands would like it better too - sometimes guys (OK, everyone) can get fixated on one thing and not really think about the larger context of what they want.
