Why does my boyfriend tell me what to wear?

As someone else said, he has an image of how a woman should look, and he's trying to make you conform to that stylized image. I would call it emotional abuse because he is never satisfied with any of your choices and he constantly puts you down. Next time just wear whatever YOU want and if he doesn't like it, too bad. You are your own person, and he has no right to criticize the way you look, especially when you spend a lot of time and money trying to please him. There's plenty of guys out there who would be perfectly happy with your look, and who would offer constructive ideas if you asked their opinion. I think you can do better than that arrogant control freak.